LSF109 - Gestion des Disques, des Systèmes de Fichiers et du Swap

Les unités de stockage sous Linux sont référencées par un des fichiers se trouvant dans le répertoire /dev :

• hd[a-d]
  • Les disques IDE et les lecteurs ATAPI
• sd[a-z]
  • Les disques SCSI et SATA
• mmcblk[0-7]
  • Les cartes SD/MMC
• scd[0-7]
  • Les CDRoms SCSI
• xd[a-d]
  • Les premiers disques sur IBM XT
• fd[0-7]
  • Les lecteurs de disquettes
• st[0-7]
  • Les lecteurs de bandes SCSI/SATA qui supportent le rembobinage
• nst[0-7]
  • Les lecteurs de bandes SCSI/SATA qui ne supportent pas le rembobinage
• ht[0-7]
  • Les lecteurs de bandes PATA qui supportent le rembobinage
• nht[0-7]
  • Les lecteurs de bandes PATA qui ne supportent pas le rembobinage
• rmt8, rmt16, tape-d, tape-reset
  • Les lecteurs QIC-80
• ram[0-15]
  • Les disques virtuels. Ils sont supprimés à l'extinction de la machine. Un de ces disques est utilisé par le système pour monter l'image d'un disque racine défini par le fichier initrd au démarrage de la machine
• Périphériques loop
  • Il existe 16 unités loop qui sont utilisés pour accèder en mode bloc à un système de fichiers contenu dans un fichier, par exemple, une image iso
• md[x]
  • Un volume RAID logiciel
• vg[x]
  • Un groupe de volumes
• lv[x]
  • Un volume logique

Un PC comportent en règle générale 2 contrôleurs de disque, chacun capable de gérer 2 disques, un maître et un esclave. Les disques attachés à ces contrôleurs comportent des noms différents pour pouvoir les distinguer :

• Contrôleur 0
  • Maître
    • hda - disque IDE
    • sda - disque SATA ou SCSI
  • Esclave
    • hdb - disque IDE
    • sdb - disque SATA ou SCSI
• Contrôleur 1
  • Maître
    • hdc - disque IDE
    • sdc - disque SATA ou SCSI
  • Esclave
    • hdd - disque IDE
    • sdd - disque SATA ou SCSI

Un disque peut comporter trois types de partitions :

• Partitions primaires,
  • Maximum de 4. En effet, la Table des Partitions est grande de 64 octets. Il faut 16 octets pour codés une partition.
• Partitions Etendues,
  • Généralement une seule partition étendue par disque. Elle contient des Lecteurs Logiques aussi appelés des partitions,
• Lecteurs Logiqiques.

Les 4 partitions primaires sont numérotées de 1 à 4. Par exemple :

• hda1, hda2, hda3 et hda4 pour le premier disque IDE sur le premier contrôleur de disque,
• sda1, sda2, sda3 et sda4 pour le premier disque SCSI ou SATA sur le premier contrôleur de disque.

Une partition étendue prend la place d'une partition primaire et les lecteurs logiques qui s'y trouvent commencent à partir de hda5 ou de sda5.

Pour clarifier ceci, considérons un disque SATA contenant deux partitions primaires, une seule partition étendue et 3 lecteurs logiques. Dans ce cas, les deux premières partitions sont sda1 et sda2, la partition étendue prend la place de la troisième partition primaire, la sda3 et s'appelle ainsi tandis que la quatrième partition primaire est inexistante.

Les lecteurs logiques commençant à sda5, nous obtenons la liste de partitions suivante : sda1, sda2, sda5, sda6, sda7. Notez que la sda3 ne peut pas être utilisée en tant que partition car elle est cachée par les lecteurs sda5, sda6 et sda7.

Le nombre de partitions sur un disque est limité :

• IDE,
  • Jusqu'à 63,
• SCSI,
  • Jusqu'à 15,
• Disques utilisant l'API libata,
  • Jusqu'à 15.

Pour procéder au partitionnement de votre disque ou de vos disques, SLES possède l'outil dénommé fdisk.

Lancez fdisk en fournissant en argument le fichier de référence de votre premier disque dur, par exemple :

SUSE12SP1:~ # fdisk /dev/sdb

Welcome to fdisk (util-linux 2.25).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.


Command (m for help):

Tapez ensuite la lettre m puis ↵ Entrée pour obtenir le menu :

Command (m for help): m

Help:

  DOS (MBR)
   a   toggle a bootable flag
   b   edit nested BSD disklabel
   c   toggle the dos compatibility flag

  Generic
   d   delete a partition
   l   list known partition types
   n   add a new partition
   p   print the partition table
   t   change a partition type
   v   verify the partition table

  Misc
   m   print this menu
   u   change display/entry units
   x   extra functionality (experts only)

  Save & Exit
   w   write table to disk and exit
   q   quit without saving changes

  Create a new label
   g   create a new empty GPT partition table
   G   create a new empty SGI (IRIX) partition table
   o   create a new empty DOS partition table
   s   create a new empty Sun partition table


Command (m for help): 

Pour créer une nouvelle partition, vous devez utiliser la commande n.

Créez donc les partitions suivantes sur votre disque :

Command (m for help): n
Partition type
   p   primary (0 primary, 0 extended, 4 free)
   e   extended (container for logical partitions)
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-41943039, default 2048): 
Last sector, +sectors or +size{K,M,G,T,P} (2048-41943039, default 41943039): +500M

Created a new partition 1 of type 'Linux' and of size 500 MiB.

Command (m for help): n
Partition type
   p   primary (1 primary, 0 extended, 3 free)
   e   extended (container for logical partitions)
Select (default p): p
Partition number (2-4, default 2): 2
First sector (1026048-41943039, default 1026048):     
Last sector, +sectors or +size{K,M,G,T,P} (1026048-41943039, default 41943039): +200M

Created a new partition 2 of type 'Linux' and of size 200 MiB.

Command (m for help): n
Partition type
   p   primary (2 primary, 0 extended, 2 free)
   e   extended (container for logical partitions)
Select (default p): p
Partition number (3,4, default 3): 3
First sector (1435648-41943039, default 1435648): 
Last sector, +sectors or +size{K,M,G,T,P} (1435648-41943039, default 41943039): +300M

Created a new partition 3 of type 'Linux' and of size 300 MiB.

Command (m for help): n   
Partition type
   p   primary (3 primary, 0 extended, 1 free)
   e   extended (container for logical partitions)
Select (default e): e

Selected partition 4
First sector (2050048-41943039, default 2050048): 
Last sector, +sectors or +size{K,M,G,T,P} (2050048-41943039, default 41943039): 

Created a new partition 4 of type 'Extended' and of size 19 GiB.

Command (m for help): n
All primary partitions are in use.
Adding logical partition 5
First sector (2052096-41943039, default 2052096): 
Last sector, +sectors or +size{K,M,G,T,P} (2052096-41943039, default 41943039): +500M

Created a new partition 5 of type 'Linux' and of size 500 MiB.

Command (m for help): n
All primary partitions are in use.
Adding logical partition 6
First sector (3078144-41943039, default 3078144): 
Last sector, +sectors or +size{K,M,G,T,P} (3078144-41943039, default 41943039): +400M

Created a new partition 6 of type 'Linux' and of size 400 MiB.

Command (m for help): n
All primary partitions are in use.
Adding logical partition 7
First sector (3899392-41943039, default 3899392): 
Last sector, +sectors or +size{K,M,G,T,P} (3899392-41943039, default 41943039): +500M

Created a new partition 7 of type 'Linux' and of size 500 MiB.

Command (m for help): n
All primary partitions are in use.
Adding logical partition 8
First sector (4925440-41943039, default 4925440): 
Last sector, +sectors or +size{K,M,G,T,P} (4925440-41943039, default 41943039): +500M

Created a new partition 8 of type 'Linux' and of size 500 MiB.

Command (m for help): n
All primary partitions are in use.
Adding logical partition 9
First sector (5951488-41943039, default 5951488): 
Last sector, +sectors or +size{K,M,G,T,P} (5951488-41943039, default 41943039): +200M

Created a new partition 9 of type 'Linux' and of size 200 MiB.

Command (m for help): 

Tapez ensuite la lettre p puis ↵ Entrée pour visualiser la nouvelle table des partitions. Vous obtiendrez un résultat similaire à celui-ci :

Command (m for help): p
Disk /dev/sdb: 20 GiB, 21474836480 bytes, 41943040 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x07e7d102

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sdb1          2048  1026047  1024000  500M 83 Linux
/dev/sdb2       1026048  1435647   409600  200M 83 Linux
/dev/sdb3       1435648  2050047   614400  300M 83 Linux
/dev/sdb4       2050048 41943039 39892992   19G  5 Extended
/dev/sdb5       2052096  3076095  1024000  500M 83 Linux
/dev/sdb6       3078144  3897343   819200  400M 83 Linux
/dev/sdb7       3899392  4923391  1024000  500M 83 Linux
/dev/sdb8       4925440  5949439  1024000  500M 83 Linux
/dev/sdb9       5951488  6361087   409600  200M 83 Linux

Command (m for help):  

Ecrivez la table des partitions sur disque et exécutez la commande partprobe :

Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

SUSE12SP1:~ # 

Lancez fdisk puis tapez ensuite la lettre p puis ↵ Entrée pour visualiser la table des partitions actuelle :

SUSE12SP1:~ # fdisk /dev/sdb

Welcome to fdisk (util-linux 2.25).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.


Command (m for help): p
Disk /dev/sdb: 20 GiB, 21474836480 bytes, 41943040 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x07e7d102

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sdb1          2048  1026047  1024000  500M 83 Linux
/dev/sdb2       1026048  1435647   409600  200M 83 Linux
/dev/sdb3       1435648  2050047   614400  300M 83 Linux
/dev/sdb4       2050048 41943039 39892992   19G  5 Extended
/dev/sdb5       2052096  3076095  1024000  500M 83 Linux
/dev/sdb6       3078144  3897343   819200  400M 83 Linux
/dev/sdb7       3899392  4923391  1024000  500M 83 Linux
/dev/sdb8       4925440  5949439  1024000  500M 83 Linux
/dev/sdb9       5951488  6361087   409600  200M 83 Linux

Command (m for help):  

Pour supprimer une partition, utilisez la commande d puis ↵ Entrée. fdisk vous demandera le numéro de la partition à supprimer, par exemple :

Command (m for help): d
Partition number (1-9, default 9): 9

Partition 9 has been deleted.

Command (m for help): p
Disk /dev/sdb: 20 GiB, 21474836480 bytes, 41943040 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x07e7d102

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sdb1          2048  1026047  1024000  500M 83 Linux
/dev/sdb2       1026048  1435647   409600  200M 83 Linux
/dev/sdb3       1435648  2050047   614400  300M 83 Linux
/dev/sdb4       2050048 41943039 39892992   19G  5 Extended
/dev/sdb5       2052096  3076095  1024000  500M 83 Linux
/dev/sdb6       3078144  3897343   819200  400M 83 Linux
/dev/sdb7       3899392  4923391  1024000  500M 83 Linux
/dev/sdb8       4925440  5949439  1024000  500M 83 Linux

Command (m for help): 

A ce stade, la partition n'a pas été réellement supprimée. En effet, vous avez la possibilité de sortir de fdisk en utilisant la commande q.

Tapez donc q pour sortir de fdisk puis relancez fdisk. Vous obtiendrez un résultat similaire à celui-ci :

Command (m for help): q

SUSE12SP1:~ # fdisk /dev/sdb

Welcome to fdisk (util-linux 2.25).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.


Command (m for help): p
Disk /dev/sdb: 20 GiB, 21474836480 bytes, 41943040 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x07e7d102

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sdb1          2048  1026047  1024000  500M 83 Linux
/dev/sdb2       1026048  1435647   409600  200M 83 Linux
/dev/sdb3       1435648  2050047   614400  300M 83 Linux
/dev/sdb4       2050048 41943039 39892992   19G  5 Extended
/dev/sdb5       2052096  3076095  1024000  500M 83 Linux
/dev/sdb6       3078144  3897343   819200  400M 83 Linux
/dev/sdb7       3899392  4923391  1024000  500M 83 Linux
/dev/sdb8       4925440  5949439  1024000  500M 83 Linux
/dev/sdb9       5951488  6361087   409600  200M 83 Linux

Command (m for help):  

Afin de mettre en place un RAID logiciel ou un volume logique, il est nécessaire de modifier les types de systèmes de fichiers sur les partitions créées.

Modifiez donc les nouvelles partitions à l'aide de la commande t de fdisk selon le tableau ci-dessous :

Vous obtiendrez un résultat similaire à celui-ci :

Command (m for help): t
Partition number (1-9, default 9): 1
Hex code (type L to list all codes): fd

Changed type of partition 'Linux' to 'Linux raid autodetect'.

Command (m for help): t
Partition number (1-9, default 9): 2
Hex code (type L to list all codes): 8e

Changed type of partition 'Linux' to 'Linux LVM'.

Command (m for help): t
Partition number (1-9, default 9): 3
Hex code (type L to list all codes): 8e

Changed type of partition 'Linux' to 'Linux LVM'.

Command (m for help): t
Partition number (1-9, default 9): 5
Hex code (type L to list all codes): fd

Changed type of partition 'Linux' to 'Linux raid autodetect'.

Command (m for help): t   
Partition number (1-9, default 9): 6
Hex code (type L to list all codes): 8e

Changed type of partition 'Linux' to 'Linux LVM'.

Command (m for help): t   
Partition number (1-9, default 9): 7
Hex code (type L to list all codes): fd

Changed type of partition 'Linux' to 'Linux raid autodetect'.

Command (m for help): t
Partition number (1-9, default 9): 8
Hex code (type L to list all codes): fd

Changed type of partition 'Linux' to 'Linux raid autodetect'.

Command (m for help): 

A l'issu des modifications, vous obtiendrez un résultat similaire à celui-ci :

Command (m for help): p
Disk /dev/sdb: 20 GiB, 21474836480 bytes, 41943040 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x07e7d102

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sdb1          2048  1026047  1024000  500M fd Linux raid autodetect
/dev/sdb2       1026048  1435647   409600  200M 8e Linux LVM
/dev/sdb3       1435648  2050047   614400  300M 8e Linux LVM
/dev/sdb4       2050048 41943039 39892992   19G  5 Extended
/dev/sdb5       2052096  3076095  1024000  500M fd Linux raid autodetect
/dev/sdb6       3078144  3897343   819200  400M 8e Linux LVM
/dev/sdb7       3899392  4923391  1024000  500M fd Linux raid autodetect
/dev/sdb8       4925440  5949439  1024000  500M fd Linux raid autodetect
/dev/sdb9       5951488  6361087   409600  200M 83 Linux

Command (m for help):  

Pour écrire la nouvelle table des partitions sur disque, vous devez utilisez la commande w puis la commande partprobe :

Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

SUSE12SP1:~ # 

Les options de cette commande sont :

SUSE12SP1:~ # fdisk --help

Usage:
 fdisk [options] <disk>      change partition table
 fdisk [options] -l [<disk>] list partition table(s)

Options:
 -b, --sector-size <size>      physical and logical sector size
 -c, --compatibility[=<mode>]  mode is 'dos' or 'nondos' (default)
 -L, --color[=<when>]          colorize output (auto, always or never)
 -l, --list                    display partitions end exit
 -t, --type <type>             recognize specified partition table type only
 -u, --units[=<unit>]          display units: 'cylinders' or 'sectors' (default)
 -s, --getsz                   display device size in 512-byte sectors [DEPRECATED]

 -C, --cylinders <number>      specify the number of cylinders
 -H, --heads <number>          specify the number of heads
 -S, --sectors <number>        specify the number of sectors per track

 -h, --help     display this help and exit
 -V, --version  output version information and exit

For more details see fdisk(8).

Afin de mettre en place le LVM, vous avez besoin du paquet lvm2 et du paquet device-mapper.

Nous allons travailler avec les partitions suivantes :

/dev/sdb2       1026048  1435647   409600  200M 8e Linux LVM
/dev/sdb3       1435648  2050047   614400  300M 8e Linux LVM
/dev/sdb6       3078144  3897343   819200  400M 8e Linux LVM

Pour initialiser le LVM saississez la commande suivante :

SUSE12SP1:~ # vgscan
  Reading all physical volumes.  This may take a while...

Les options de la commande vgscan sont :

SUSE12SP1:~ # vgscan --help
  vgscan: Search for all volume groups

vgscan 	[--cache]
	[--commandprofile ProfileName]
	[-d|--debug]
	[-h|--help]
	[--ignorelockingfailure]
	[--mknodes]
	[-P|--partial]
	[-v|--verbose]
	[--version]

Pour créer le PV il convient d'utiliser la commande pvcreate :

SUSE12SP1:~ # pvcreate /dev/sdb2 /dev/sdb3 /dev/sdb6
  Physical volume "/dev/sdb2" successfully created
  Physical volume "/dev/sdb3" successfully created
  Physical volume "/dev/sdb6" successfully created

Les options de la commande pvcreate sont :

SUSE12SP1:~ # pvcreate --help
  pvcreate: Initialize physical volume(s) for use by LVM

pvcreate
	[--norestorefile]
	[--restorefile file]
	[--commandprofile ProfileName]
	[-d|--debug]
	[-f[f]|--force [--force]]
	[-h|-?|--help]
	[--labelsector sector]
	[-M|--metadatatype 1|2]
	[--pvmetadatacopies #copies]
	[--bootloaderareasize BootLoaderAreaSize[bBsSkKmMgGtTpPeE]]
	[--metadatasize MetadataSize[bBsSkKmMgGtTpPeE]]
	[--dataalignment Alignment[bBsSkKmMgGtTpPeE]]
	[--dataalignmentoffset AlignmentOffset[bBsSkKmMgGtTpPeE]]
	[--setphysicalvolumesize PhysicalVolumeSize[bBsSkKmMgGtTpPeE]
	[-t|--test]
	[-u|--uuid uuid]
	[-v|--verbose]
	[-y|--yes]
	[-Z|--zero {y|n}]
	[--version]
	PhysicalVolume [PhysicalVolume...]

Pour visualiser le PV il convient d'utiliser la commande pvdisplay :

SUSE12SP1:~ # pvdisplay /dev/sdb2 /dev/sdb3 /dev/sdb6
  "/dev/sdb3" is a new physical volume of "300.00 MiB"
  --- NEW Physical volume ---
  PV Name               /dev/sdb3
  VG Name               
  PV Size               300.00 MiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               lnUsag-cM0o-76LP-PffQ-wJQK-0NKa-vjtFzy
   
  "/dev/sdb6" is a new physical volume of "400.00 MiB"
  --- NEW Physical volume ---
  PV Name               /dev/sdb6
  VG Name               
  PV Size               400.00 MiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               fO06lr-O2qe-ccmx-4JV6-98zm-CGBr-EWQUho
   
  "/dev/sdb2" is a new physical volume of "200.00 MiB"
  --- NEW Physical volume ---
  PV Name               /dev/sdb2
  VG Name               
  PV Size               200.00 MiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               SdDEnc-2fiL-IY82-K0zp-MSCx-w1Nj-zefWFA

Les options de la commande pvdisplay sont :

SUSE12SP1:~ # pvdisplay --help
  pvdisplay: Display various attributes of physical volume(s)

pvdisplay
	[-c|--colon]
	[--commandprofile ProfileName]
	[-d|--debug]
	[--foreign]
	[-h|--help]
	[--ignorelockingfailure]
	[--ignoreskippedcluster]
	[-m|--maps]
	[--nosuffix]
	[--readonly]
	[-S|--select Selection]
	[-s|--short]
	[--units hHbBsSkKmMgGtTpPeE]
	[-v|--verbose]
	[--version]
	[PhysicalVolumePath [PhysicalVolumePath...]]

pvdisplay --columns|-C
	[--aligned]
	[-a|--all]
	[--binary]
	[--commandprofile ProfileName]
	[-d|--debug]
	[--foreign]
	[-h|--help]
	[--ignorelockingfailure]
	[--ignoreskippedcluster]
	[--noheadings]
	[--nosuffix]
	[-o|--options [+]Field[,Field]]
	[-O|--sort [+|-]key1[,[+|-]key2[,...]]]
	[-S|--select Selection]
	[--readonly]
	[--separator Separator]
	[--unbuffered]
	[--units hHbBsSkKmMgGtTpPeE]
	[-v|--verbose]
	[--version]
	[PhysicalVolumePath [PhysicalVolumePath...]]

Pour créer un Volume Group dénommé vg0, il convient d'utiliser la commande vgcreate :

SUSE12SP1:~ # vgcreate -s 8M vg0 /dev/sdb2 /dev/sdb3 /dev/sdb6
  Volume group "vg0" successfully created

Les options de la commande vgcreate sont :

SUSE12SP1:~ # vgcreate --help
  vgcreate: Create a volume group

vgcreate
	[-A|--autobackup {y|n}]
	[--addtag Tag]
	[--alloc AllocationPolicy]
	[-c|--clustered {y|n}]
	[--commandprofile ProfileName]
	[-d|--debug]
	[-h|--help]
	[-l|--maxlogicalvolumes MaxLogicalVolumes]
	[--metadataprofile ProfileName]
	[-M|--metadatatype 1|2]
	[--[vg]metadatacopies #copies]
	[-p|--maxphysicalvolumes MaxPhysicalVolumes]
	[-s|--physicalextentsize PhysicalExtentSize[bBsSkKmMgGtTpPeE]]
	[--systemid SystemID]
	[-t|--test]
	[-v|--verbose]
	[--version]
	[-y|--yes]
	[ PHYSICAL DEVICE OPTIONS ]
	VolumeGroupName PhysicalDevicePath [PhysicalDevicePath...]

Pour afficher les informations concernant vg0, il convient d'utiliser la commande vgdisplay :

SUSE12SP1:~ # vgdisplay vg0
  --- Volume group ---
  VG Name               vg0
  System ID             
  Format                lvm2
  Metadata Areas        3
  Metadata Sequence No  1
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                0
  Open LV               0
  Max PV                0
  Cur PV                3
  Act PV                3
  VG Size               880.00 MiB
  PE Size               8.00 MiB
  Total PE              110
  Alloc PE / Size       0 / 0   
  Free  PE / Size       110 / 880.00 MiB
  VG UUID               Nlcq1a-DCcC-2zsF-Xjn7-vqPJ-XmIO-1wI6p8

Les options de la commande vgdisplay sont :

SUSE12SP1:~ # vgdisplay --help
  vgdisplay: Display volume group information

vgdisplay
	[-A|--activevolumegroups]
	[-c|--colon | -s|--short | -v|--verbose]
	[--commandprofile ProfileName]
	[-d|--debug]
	[--foreign]
	[-h|--help]
	[--ignorelockingfailure]
	[--ignoreskippedcluster]
	[--nosuffix]
	[-P|--partial]
	[--readonly]
	[-S|--select Selection]
	[--units hHbBsSkKmMgGtTpPeE]
	[--version]
	[VolumeGroupName [VolumeGroupName...]]

vgdisplay --columns|-C
	[--aligned]
	[--binary]
	[--commandprofile ProfileName]
	[-d|--debug]
	[--foreign]
	[-h|--help]
	[--ignorelockingfailure]
	[--ignoreskippedcluster]
	[--noheadings]
	[--nosuffix]
	[-o|--options [+]Field[,Field]]
	[-O|--sort [+|-]key1[,[+|-]key2[,...]]]
	[-P|--partial]
	[-S|--select Selection]
	[--readonly]
	[--separator Separator]
	[--unbuffered]
	[--units hHbBsSkKmMgGtTpPeE]
	[--verbose]
	[--version]
	[VolumeGroupName [VolumeGroupName...]]

Pour créer un Logical Volume dénommé lv0 dans le Volume Group vg0, il convient d'utiliser la commande lvcreate :

SUSE12SP1:~ # lvcreate -L 350 -n lv0 vg0
  Rounding up size to full physical extent 352.00 MiB
  Logical volume "lv0" created.

Les options de la commande lvcreate sont :

SUSE12SP1:~ # lvcreate --help
  lvcreate: Create a logical volume

lvcreate
	[-A|--autobackup {y|n}]
	[-a|--activate [a|e|l]{y|n}]
	[--addtag Tag]
	[--alloc AllocationPolicy]
	[-H|--cache
	  [--cachemode {writeback|writethrough}]
	[--cachepool CachePoolLogicalVolume{Name|Path}]
	[-c|--chunksize ChunkSize]
	[-C|--contiguous {y|n}]
	[--commandprofile ProfileName]
	[-d|--debug]
	[-h|-?|--help]
	[--errorwhenfull {y|n}]
	[--ignoremonitoring]
	[--monitor {y|n}]
	[-i|--stripes Stripes [-I|--stripesize StripeSize]]
	[-k|--setactivationskip {y|n}]
	[-K|--ignoreactivationskip]
	{-l|--extents LogicalExtentsNumber[%{VG|PVS|FREE}] |
	 -L|--size LogicalVolumeSize[bBsSkKmMgGtTpPeE]}
	[-M|--persistent {y|n}] [-j|--major major] [--minor minor]
	[--metadataprofile ProfileName]
	[-m|--mirrors Mirrors [--nosync]
	  [{--mirrorlog {disk|core|mirrored}|--corelog}]]
	[-n|--name LogicalVolumeName]
	[--noudevsync]
	[-p|--permission {r|rw}]
	[--poolmetadatasize MetadataSize[bBsSkKmMgG]]
	[--poolmetadataspare {y|n}]]
	[--[raid]minrecoveryrate Rate]
	[--[raid]maxrecoveryrate Rate]
	[-r|--readahead {ReadAheadSectors|auto|none}]
	[-R|--regionsize MirrorLogRegionSize]
	[-T|--thin
	  [--discards {ignore|nopassdown|passdown}]
	[--thinpool ThinPoolLogicalVolume{Name|Path}]
	[-t|--test]
	[--type VolumeType]
	[-v|--verbose]
	[-W|--wipesignatures {y|n}]
	[-Z|--zero {y|n}]
	[--version]
	VolumeGroupName [PhysicalVolumePath...]

lvcreate
	{ {-s|--snapshot} OriginalLogicalVolume[Path] |
	  [-s|--snapshot] VolumeGroupName[Path] -V|--virtualsize VirtualSize}
	  {-H|--cache} VolumeGroupName[Path][/OriginalLogicalVolume]
	  {-T|--thin} VolumeGroupName[Path][/PoolLogicalVolume]
	              -V|--virtualsize VirtualSize}
	[-A|--autobackup {y|n}]
	[--addtag Tag]
	[--alloc AllocationPolicy]
	[--cachepolicy Policy] [--cachesettings Key=Value]
	[-c|--chunksize]
	[-C|--contiguous {y|n}]
	[--commandprofile ProfileName]
	[-d|--debug]
	[--discards {ignore|nopassdown|passdown}]
	[-h|-?|--help]
	[--ignoremonitoring]
	[--monitor {y|n}]
	[-i|--stripes Stripes [-I|--stripesize StripeSize]]
	[-k|--setactivationskip {y|n}]
	[-K|--ignoreactivationskip]
	{-l|--extents LogicalExtentsNumber[%{VG|FREE|ORIGIN}] |
	 -L|--size LogicalVolumeSize[bBsSkKmMgGtTpPeE]}
	[--poolmetadatasize MetadataVolumeSize[bBsSkKmMgG]]
	[-M|--persistent {y|n}] [-j|--major major] [--minor minor]
	[--metadataprofile ProfileName]
	[-n|--name LogicalVolumeName]
	[--noudevsync]
	[-p|--permission {r|rw}]
	[-r|--readahead ReadAheadSectors|auto|none]
	[-t|--test]
	[{--thinpool ThinPoolLogicalVolume[Path] |
	  --cachepool CachePoolLogicalVolume[Path]}]
	[-v|--verbose]
	[--version]
	[PhysicalVolumePath...]

Créez maintenant un répertoire dans /mnt pour monter lv0 :

SUSE12SP1:~ # mkdir /mnt/lvm

Créez un système de fichiers en ext3 sur /dev/vg0/lv0 :

SUSE12SP1:~ # mke2fs -j /dev/vg0/lv0
mke2fs 1.42.11 (09-Jul-2014)
Creating filesystem with 360448 1k blocks and 90112 inodes
Filesystem UUID: 07f7376a-11b8-46dc-bd1d-f6a7a5aa3e11
Superblock backups stored on blocks: 
	8193, 24577, 40961, 57345, 73729, 204801, 221185

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done

Montez votre lv0 :

SUSE12SP1:~ # mount -t ext3 /dev/vg0/lv0 /mnt/lvm

Vous allez maintenant copier le contenu de votre répertoire /home vers /mnt/lvm.

Saisissez donc la commande pour copier le contenu de /home :

SUSE12SP1:~ # cp -a /home /mnt/lvm

Constatez ensuite le contenu de /mnt/lvm :

SUSE12SP1:~ # ls -l /mnt/lvm
total 13
drwxr-xr-x 3 root root  1024 Oct  9 11:57 home
drwx------ 2 root root 12288 Oct 10 16:38 lost+found

Une particularité du volume logique est la capacité de d'être aggrandi ou réduit sans pertes de données. Commencez par constater la taille totale du volume :

SUSE12SP1:~ # df -h /mnt/lvm
Filesystem           Size  Used Avail Use% Mounted on
/dev/mapper/vg0-lv0  333M  2.6M  313M   1% /mnt/lvm

Dans la cas de notre exemple, la taille est de 333 Mo avec 2,6 Mo occupé.

Pour agrandir un volume logique, le paquet lvm2 contient les commandes lvextend et resize2fs :

SUSE12SP1:~ # lvextend -L +100M /dev/vg0/lv0
  Rounding size to boundary between physical extents: 104.00 MiB
  Size of logical volume vg0/lv0 changed from 352.00 MiB (44 extents) to 456.00 MiB (57 extents).
  Logical volume lv0 successfully resized

Les options de la commande lvextend sont :

SUSE12SP1:~ # lvextend --help
  lvextend: Add space to a logical volume

lvextend
	[-A|--autobackup y|n]
	[--alloc AllocationPolicy]
	[--commandprofile ProfileName]
	[-d|--debug]
	[-f|--force]
	[-h|--help]
	[-i|--stripes Stripes [-I|--stripesize StripeSize]]
	{-l|--extents [+]LogicalExtentsNumber[%{VG|LV|PVS|FREE|ORIGIN}] |
	 -L|--size [+]LogicalVolumeSize[bBsSkKmMgGtTpPeE]}
	 --poolmetadatasize [+]MetadataVolumeSize[bBsSkKmMgG]}
	[-m|--mirrors Mirrors]
	[--nosync]
	[--use-policies]
	[-n|--nofsck]
	[--noudevsync]
	[-r|--resizefs]
	[-t|--test]
	[--type VolumeType]
	[-v|--verbose]
	[--version]
	LogicalVolume[Path] [ PhysicalVolumePath... ]

Le volume ayant été agrandi, il est necessaire maintenant d'agrandir le filesystem qui s'y trouve :

SUSE12SP1:~ # resize2fs /dev/vg0/lv0
resize2fs 1.42.11 (09-Jul-2014)
Filesystem at /dev/vg0/lv0 is mounted on /mnt/lvm; on-line resizing required
old_desc_blocks = 2, new_desc_blocks = 2
The filesystem on /dev/vg0/lv0 is now 466944 blocks long.

Constatez maintenant la modification de la taille du volume :

SUSE12SP1:~ # df -h /mnt/lvm
Filesystem           Size  Used Avail Use% Mounted on
/dev/mapper/vg0-lv0  434M  2.8M  410M   1% /mnt/lvm

Vous noterez que la taille a augmentée mais que les données sont toujours présentes.

Un snapshot est un instantané d'un système de fichiers. Dans cet exemple, vous allez créer un snapshot de votre lv0 :

Avant de commencer, créez un fichier de 10Mo dans le volume :

SUSE12SP1:~ # dd if=/dev/zero of=/mnt/lvm/10M bs=1048576 count=10
10+0 records in
10+0 records out
10485760 bytes (10 MB) copied, 0.101338 s, 103 MB/s

Créez maintenant un snapshot :

SUSE12SP1:~ # lvcreate -s -L 15M -n testsnap /dev/vg0/lv0
  Rounding up size to full physical extent 16.00 MiB
  Logical volume "testsnap" created.

Pour avoir une confirmation de la création du snapshot, utilisez la commande lvs :

SUSE12SP1:~ # lvs
  LV       VG   Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  lv0      vg0  owi-aos--- 456.00m                                                    
  testsnap vg0  swi-a-s---  16.00m      lv0    0.07    

Les options de la commande lvs sont :

SUSE12SP1:~ # lvs --help
  lvs: Display information about logical volumes

lvs
	[-a|--all]
	[--aligned]
	[--binary]
	[--commandprofile ProfileName]
	[-d|--debug]
	[--foreign]
	[-h|--help]
	[--ignorelockingfailure]
	[--ignoreskippedcluster]
	[--nameprefixes]
	[--noheadings]
	[--nosuffix]
	[-o|--options [+]Field[,Field]]
	[-O|--sort [+|-]key1[,[+|-]key2[,...]]]
	[-P|--partial]
	[--readonly]
	[--rows]
	[--segments]
	[-S|--select Selection]
	[--separator Separator]
	[--trustcache]
	[--unbuffered]
	[--units hHbBsSkKmMgGtTpPeE]
	[--unquoted]
	[-v|--verbose]
	[--version]
	[LogicalVolume[Path] [LogicalVolume[Path]...]]

Créez maintenant un répertoire pour monter le snapshot :

SUSE12SP1:~ # mkdir /mnt/testsnap

Montez le snapshot :

SUSE12SP1:~ # mount /dev/vg0/testsnap /mnt/testsnap

Comparez le volume d'origine et le snapshot :

SUSE12SP1:~ # ls -l /mnt/lvm
total 10294
-rw-r--r-- 1 root root 10485760 Oct 10 17:07 10M
drwxr-xr-x 3 root root     1024 Oct  9 11:57 home
drwx------ 2 root root    12288 Oct 10 16:38 lost+found
SUSE12SP1:~ # ls -l /mnt/testsnap
total 10294
-rw-r--r-- 1 root root 10485760 Oct 10 17:07 10M
drwxr-xr-x 3 root root     1024 Oct  9 11:57 home
drwx------ 2 root root    12288 Oct 10 16:38 lost+found

Supprimez maintenant le fichier 10M de votre volume d'origine :

SUSE12SP1:~ # rm /mnt/lvm/10M

Constatez le résultat de cette suppression :

SUSE12SP1:~ # df -Ph /mnt/lvm
Filesystem           Size  Used Avail Use% Mounted on
/dev/mapper/vg0-lv0  434M  2.8M  410M   1% /mnt/lvm
SUSE12SP1:~ # 
SUSE12SP1:~ # df -Ph /mnt/testsnap
Filesystem                Size  Used Avail Use% Mounted on
/dev/mapper/vg0-testsnap  434M   13M  400M   4% /mnt/testsnap
SUSE12SP1:~ # 
SUSE12SP1:~ # lvs
  LV       VG   Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  lv0      vg0  owi-aos--- 456.00m                                                    
  testsnap vg0  swi-aos---  16.00m      lv0    0.32    

La suppression d'un volume logique se fait grace à la commande lvremove :

SUSE12SP1:~ # umount /mnt/testsnap/
SUSE12SP1:~ # lvremove /dev/vg0/testsnap
Do you really want to remove active logical volume testsnap? [y/n]: y
  Logical volume "testsnap" successfully removed
SUSE12SP1:~ # umount /mnt/lvm
SUSE12SP1:~ # lvremove /dev/vg0/lv0
Do you really want to remove active logical volume lv0? [y/n]: y
  Logical volume "lv0" successfully removed

Les options de la commande lvremove sont :

SUSE12SP1:~ # lvremove --help
  lvremove: Remove logical volume(s) from the system

lvremove
	[-A|--autobackup y|n]
	[--commandprofile ProfileName]
	[-d|--debug]
	[-f|--force]
	[-h|--help]
	[--noudevsync]
	[-S|--select Selection]
	[-t|--test]
	[-v|--verbose]
	[--version]
	LogicalVolume[Path] [LogicalVolume[Path]...]

Le Volume Group peut aussi être supprimé :

SUSE12SP1:~ # vgremove vg0
  Volume group "vg0" successfully removed

Les options de la commande vgremove sont :

SUSE12SP1:~ # vgremove --help
  vgremove: Remove volume group(s)

vgremove
	[--commandprofile ProfileName]
	[-d|--debug]
	[-f|--force]
	[-h|--help]
	[--noudevsync]
	[-S|--select Selection]
	[-t|--test]
	[-v|--verbose]
	[--version]
	VolumeGroupName [VolumeGroupName...]

Ainsi que le volume physique :

SUSE12SP1:~ # pvremove /dev/sdb2 /dev/sdb3 /dev/sdb6
  Labels on physical volume "/dev/sdb2" successfully wiped
  Labels on physical volume "/dev/sdb3" successfully wiped
  Labels on physical volume "/dev/sdb6" successfully wiped

Les options de la commande pvremove sont :

SUSE12SP1:~ # pvremove --help
  pvremove: Remove LVM label(s) from physical volume(s)

pvremove
	[--commandprofile ProfileName]
	[-d|--debug]
	[-f[f]|--force [--force]]
	[-h|-?|--help]
	[-t|--test]
	[-v|--verbose]
	[--version]
	[-y|--yes]
	PhysicalVolume [PhysicalVolume...]

Re-créez maintenant votre Volume Group :

SUSE12SP1:~ # pvcreate /dev/sdb2 /dev/sdb3 /dev/sdb6
  Physical volume "/dev/sdb2" successfully created
  Physical volume "/dev/sdb3" successfully created
  Physical volume "/dev/sdb6" successfully created
SUSE12SP1:~ # vgcreate -s 8M vg0 /dev/sdb2 /dev/sdb3 /dev/sdb6
  Volume group "vg0" successfully created

Créez maintenant un Logical Volume en miroir grâce à l'option -m de la commande lvcreate, suivi du nombre de miroirs :

SUSE12SP1:~ # lvcreate -m 1 -L 100M -n lv1 vg0
  Rounding up size to full physical extent 104.00 MiB
  Logical volume "lv1" created.

Constatez miantenant la présence du miroir :

SUSE12SP1:~ # lvdisplay -m /dev/vg0/lv1
  --- Logical volume ---
  LV Path                /dev/vg0/lv1
  LV Name                lv1
  VG Name                vg0
  LV UUID                GACvjV-rvto-MBTS-xnsn-7A3e-40JC-vLWh13
  LV Write Access        read/write
  LV Creation host, time SUSE12SP1.fenestros.loc, 2017-10-11 09:49:30 +0200
  LV Status              available
  # open                 0
  LV Size                104.00 MiB
  Current LE             13
  Mirrored volumes       2
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     1024
  Block device           254:4
   
  --- Segments ---
  Logical extents 0 to 12:
    Type		raid1
    Monitoring		monitored
    Raid Data LV 0
      Logical volume	lv1_rimage_0
      Logical extents	0 to 12
    Raid Data LV 1
      Logical volume	lv1_rimage_1
      Logical extents	0 to 12
    Raid Metadata LV 0	lv1_rmeta_0
    Raid Metadata LV 1	lv1_rmeta_1

Le miroir s'étend sur plusieurs volumes physiques :

SUSE12SP1:~ # pvdisplay -m /dev/sdb2 /dev/sdb3 /dev/sdb6
  --- Physical volume ---
  PV Name               /dev/sdb2
  VG Name               vg0
  PV Size               200.00 MiB / not usable 8.00 MiB
  Allocatable           yes 
  PE Size               8.00 MiB
  Total PE              24
  Free PE               10
  Allocated PE          14
  PV UUID               408GSr-a47G-cjbB-Vrpd-OfXs-pqZs-l0A7pW
   
  --- Physical Segments ---
  Physical extent 0 to 0:
    Logical volume	/dev/vg0/lv1_rmeta_0
    Logical extents	0 to 0
  Physical extent 1 to 13:
    Logical volume	/dev/vg0/lv1_rimage_0
    Logical extents	0 to 12
  Physical extent 14 to 23:
    FREE
   
  --- Physical volume ---
  PV Name               /dev/sdb3
  VG Name               vg0
  PV Size               300.00 MiB / not usable 4.00 MiB
  Allocatable           yes 
  PE Size               8.00 MiB
  Total PE              37
  Free PE               23
  Allocated PE          14
  PV UUID               YU3YJD-s1nB-wAYz-e329-UcgK-je8c-aXwngf
   
  --- Physical Segments ---
  Physical extent 0 to 0:
    Logical volume	/dev/vg0/lv1_rmeta_1
    Logical extents	0 to 0
  Physical extent 1 to 13:
    Logical volume	/dev/vg0/lv1_rimage_1
    Logical extents	0 to 12
  Physical extent 14 to 36:
    FREE
   
  --- Physical volume ---
  PV Name               /dev/sdb6
  VG Name               vg0
  PV Size               400.00 MiB / not usable 8.00 MiB
  Allocatable           yes 
  PE Size               8.00 MiB
  Total PE              49
  Free PE               49
  Allocated PE          0
  PV UUID               QgKnsv-ZW3O-YEaw-LNfY-ZyTt-WXHw-D8StdG
   
  --- Physical Segments ---
  Physical extent 0 to 48:
    FREE

La suppression du miroir se fait en utilisant la commande lvconvert en indiquant quel volume physique doit être vidé de son contenu :

SUSE12SP1:~ # lvconvert -m 0 /dev/vg0/lv1 /dev/sdb3

De même, il est possible de créer un miroir pour un volume logique existant :

SUSE12SP1:~ # lvconvert -m 1 /dev/vg0/lv1

Supprimez de nouveau votre miroir :

SUSE12SP1:~ # lvconvert -m 0 /dev/vg0/lv1 /dev/sdb3

Les options de la commande lvconvert sont :

SUSE12SP1:~ # lvconvert --help
  lvconvert: Change logical volume layout

lvconvert [-m|--mirrors Mirrors [{--mirrorlog {disk|core|mirrored}|--corelog}]]
	[--type SegmentType]
	[--repair [--use-policies]]
	[--replace PhysicalVolume]
	[-R|--regionsize MirrorLogRegionSize]
	[--alloc AllocationPolicy]
	[-b|--background]
	[-f|--force]
	[-i|--interval seconds]
	[--stripes Stripes [-I|--stripesize StripeSize]]
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	LogicalVolume[Path] [PhysicalVolume[Path]...]

lvconvert [--splitmirrors Images --trackchanges]
	[--splitmirrors Images --name SplitLogicalVolumeName]
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	LogicalVolume[Path] [SplittablePhysicalVolume[Path]...]

lvconvert --splitsnapshot
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	SnapshotLogicalVolume[Path]

lvconvert --splitcache
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	CacheLogicalVolume[Path]

lvconvert --split
	[--name SplitLogicalVolumeName]
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	SplitableLogicalVolume[Path]

lvconvert --uncache
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	CacheLogicalVolume[Path]

lvconvert [--type snapshot|-s|--snapshot]
	[-c|--chunksize]
	[-Z|--zero {y|n}]
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	OriginalLogicalVolume[Path] SnapshotLogicalVolume[Path]

lvconvert --merge
	[-b|--background]
	[-i|--interval seconds]
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	LogicalVolume[Path]

lvconvert [--type thin[-pool]|-T|--thin]
	[--thinpool ThinPoolLogicalVolume[Path]]
	[--chunksize size]
	[--discards {ignore|nopassdown|passdown}]
	[--poolmetadataspare {y|n}]
	[{--poolmetadata ThinMetadataLogicalVolume[Path] |
	 --poolmetadatasize size}]
	[-r|--readahead ReadAheadSectors|auto|none]
	[--stripes Stripes [-I|--stripesize StripeSize]]]
	[--originname NewExternalOriginVolumeName]]
	[-Z|--zero {y|n}]
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	[ExternalOrigin|ThinDataPool]LogicalVolume[Path] [PhysicalVolumePath...]

lvconvert [--type cache[-pool]|-H|--cache]
	[--cachepool CacheDataLogicalVolume[Path]]
	[--cachemode CacheMode]
	[--chunksize size]
	[--poolmetadataspare {y|n}]]
	[{--poolmetadata CacheMetadataLogicalVolume[Path] |
	 --poolmetadatasize size}]
	[--commandprofile ProfileName] [-d|--debug] [-h|-?|--help]
	[--noudevsync] [-t|--test] [-v|--verbose] [--version] [-y|--yes]
	[Cache|CacheDataPool]LogicalVolume[Path] [PhysicalVolumePath...]

En cas de présence d'un miroir, la commande lvs indique la présence du miroir dans la colonne Attr avec la lettre m :

SUSE12SP1:~ # lvs
  LV   VG   Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  lv1  vg0  -wi-a----- 104.00m       

La commande equivalente pour les Volume Groups est vgs :

SUSE12SP1:~ # vgs
  VG   #PV #LV #SN Attr   VSize   VFree  
  vg0    3   1   0 wz--n- 880.00m 776.00m

La commande equivalente pour les Physical Volumes est pvs :

SUSE12SP1:~ # pvs
  PV         VG   Fmt  Attr PSize   PFree  
  /dev/sdb2  vg0  lvm2 a--  192.00m  88.00m
  /dev/sdb3  vg0  lvm2 a--  296.00m 296.00m
  /dev/sdb6  vg0  lvm2 a--  392.00m 392.00m

Les commandes lvchange, vgchange et pvchange permettent de modifier les attributs des Logical Volumes, Volume Groups et Physical Volumes respectivement.

Par exemple, pour rendre inutilisable un Logical Volume, il convient d'enlever l'attribut a :

SUSE12SP1:~ # lvchange -a n /dev/vg0/lv1
SUSE12SP1:~ # lvs
  LV   VG   Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  lv1  vg0  -wi------- 104.00m 

Pour faire l'inverse il convient de saisir la commande suivante :

SUSE12SP1:~ # lvchange -a y /dev/vg0/lv1
SUSE12SP1:~ # lvs
  LV   VG   Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  lv1  vg0  -wi-a----- 104.00m  

Les options de la commande lvchange sont :

SUSE12SP1:~ # lvchange --help
  lvchange: Change the attributes of logical volume(s)

lvchange
	[-A|--autobackup y|n]
	[-a|--activate [a|e|l]{y|n}]
	[--activationmode {complete|degraded|partial}	[--addtag Tag]
	[--alloc AllocationPolicy]
	[-C|--contiguous y|n]
	[--cachepolicy policyname] [--cachesettings parameter=value]
	[--commandprofile ProfileName]
	[-d|--debug]
	[--deltag Tag]
	[--detachprofile]
	[--errorwhenfull {y|n}]
	[-f|--force]
	[-h|--help]
	[--discards {ignore|nopassdown|passdown}]
	[--ignorelockingfailure]
	[--ignoremonitoring]
	[--ignoreskippedcluster]
	[-k|--setactivationskip {y|n}]
	[-K|--ignoreactivationskip]
	[--monitor {y|n}]
	[--poll {y|n}]
	[--noudevsync]
	[-M|--persistent y|n] [-j|--major major] [--minor minor]
	[--metadataprofile ProfileName]
	[-P|--partial]
	[-p|--permission r|rw]
	[--[raid]minrecoveryrate Rate]
	[--[raid]maxrecoveryrate Rate]
	[--[raid]syncaction {check|repair}
	[--[raid]writebehind IOCount]
	[--[raid]writemostly PhysicalVolume[:{t|n|y}]]
	[-r|--readahead ReadAheadSectors|auto|none]
	[--refresh]
	[--resync]
	[-S|--select Selection]
	[--sysinit]
	[-t|--test]
	[-v|--verbose]
	[--version]
	[-y|--yes]
	[-Z|--zero {y|n}]
	LogicalVolume[Path] [LogicalVolume[Path]...]

Un volume logique en bandes est créé pour augmenter, comme dans le cas du RAID, les performances des entrées et sorties. Pour créer ce volume, la commande lvcreate prend deux option supplémentaires :

• -i - indique le nombre de volumes de bandes,
• -I - indique la taille en Ko de chaque bande.

Saisissez donc la commande suivante :

SUSE12SP1:~ # lvcreate -i2 -I64 -n lv2 -L 100M vg0 /dev/sdb3 /dev/sdb6
  Rounding up size to full physical extent 104.00 MiB
  Rounding size (13 extents) up to stripe boundary size (14 extents).
  Logical volume "lv2" created.

Constatez la présence de vos bandes sur /dev/sda7 et sur /dev/sda9 :

SUSE12SP1:~ # lvdisplay -m /dev/vg0/lv2
  --- Logical volume ---
  LV Path                /dev/vg0/lv2
  LV Name                lv2
  VG Name                vg0
  LV UUID                PQ175n-zCmp-78Yi-t2dz-YOv5-1Waq-K4NVOF
  LV Write Access        read/write
  LV Creation host, time SUSE12SP1.fenestros.loc, 2017-10-11 09:59:20 +0200
  LV Status              available
  # open                 0
  LV Size                112.00 MiB
  Current LE             14
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     1024
  Block device           254:1
   
  --- Segments ---
  Logical extents 0 to 13:
    Type		striped
    Stripes		2
    Stripe size		64.00 KiB
    Stripe 0:
      Physical volume	/dev/sdb3
      Physical extents	0 to 6
    Stripe 1:
      Physical volume	/dev/sdb6
      Physical extents	0 to 6

Utilisez maintenant la commande lvs pour visualiser les volumes physiques utilisés par le volume logique :

SUSE12SP1:~ # lvs -o +devices
  LV   VG   Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert Devices                  
  lv1  vg0  -wi-a----- 104.00m                                                     /dev/sdb2(1)             
  lv2  vg0  -wi-a----- 112.00m                                                     /dev/sdb3(0),/dev/sdb6(0)

Les métadonnées pour chaque Volume Group sont stockés dans un fichier texte au nom du Volume Group dans le répertoire /etc/lvm/backup :

SUSE12SP1:~ # cat /etc/lvm/backup/vg0
# Generated by LVM2 version 2.02.120(2) (2015-05-15): Wed Oct 11 09:59:20 2017

contents = "Text Format Volume Group"
version = 1

description = "Created *after* executing 'lvcreate -i2 -I64 -n lv2 -L 100M vg0 /dev/sdb3 /dev/sdb6'"

creation_host = "SUSE12SP1.fenestros.loc"	# Linux SUSE12SP1.fenestros.loc 3.12.74-60.64.40-default #1 SMP Wed May 10 05:07:16 UTC 2017 (4eb35ec) x86_64
creation_time = 1507708760	# Wed Oct 11 09:59:20 2017

vg0 {
	id = "qCdv6F-cMd5-j2de-u91l-AgpE-3NCQ-J6G33P"
	seqno = 10
	format = "lvm2"			# informational
	status = ["RESIZEABLE", "READ", "WRITE"]
	flags = []
	extent_size = 16384		# 8 Megabytes
	max_lv = 0
	max_pv = 0
	metadata_copies = 0

	physical_volumes {

		pv0 {
			id = "408GSr-a47G-cjbB-Vrpd-OfXs-pqZs-l0A7pW"
			device = "/dev/sdb2"	# Hint only

			status = ["ALLOCATABLE"]
			flags = []
			dev_size = 409600	# 200 Megabytes
			pe_start = 2048
			pe_count = 24	# 192 Megabytes
		}

		pv1 {
			id = "YU3YJD-s1nB-wAYz-e329-UcgK-je8c-aXwngf"
			device = "/dev/sdb3"	# Hint only

			status = ["ALLOCATABLE"]
			flags = []
			dev_size = 614400	# 300 Megabytes
			pe_start = 2048
			pe_count = 37	# 296 Megabytes
		}

		pv2 {
			id = "QgKnsv-ZW3O-YEaw-LNfY-ZyTt-WXHw-D8StdG"
			device = "/dev/sdb6"	# Hint only

			status = ["ALLOCATABLE"]
			flags = []
			dev_size = 819200	# 400 Megabytes
			pe_start = 2048
			pe_count = 49	# 392 Megabytes
		}
	}

	logical_volumes {

		lv1 {
			id = "GACvjV-rvto-MBTS-xnsn-7A3e-40JC-vLWh13"
			status = ["READ", "WRITE", "VISIBLE"]
			flags = []
			creation_host = "SUSE12SP1.fenestros.loc"
			creation_time = 1507708170	# 2017-10-11 09:49:30 +0200
			segment_count = 1

			segment1 {
				start_extent = 0
				extent_count = 13	# 104 Megabytes

				type = "striped"
				stripe_count = 1	# linear

				stripes = [
					"pv0", 1
				]
			}
		}

		lv2 {
			id = "PQ175n-zCmp-78Yi-t2dz-YOv5-1Waq-K4NVOF"
			status = ["READ", "WRITE", "VISIBLE"]
			flags = []
			creation_host = "SUSE12SP1.fenestros.loc"
			creation_time = 1507708760	# 2017-10-11 09:59:20 +0200
			segment_count = 1

			segment1 {
				start_extent = 0
				extent_count = 14	# 112 Megabytes

				type = "striped"
				stripe_count = 2
				stripe_size = 128	# 64 Kilobytes

				stripes = [
					"pv1", 0,
					"pv2", 0
				]
			}
		}
	}
}

Des archives sont créées lors de chaque modification d'un groupe de volumes et elles sont placés dans le répertoire /etc/lvm/archives :

SUSE12SP1:~ # ls /etc/lvm/archive/
vg0_00000-1490864187.vg  vg0_00005-1861990860.vg  vg0_00010-1593394958.vg
vg0_00001-1258721014.vg  vg0_00006-475023216.vg   vg0_00011-1525730672.vg
vg0_00002-1552831049.vg  vg0_00007-1421103332.vg  vg0_00012-1449042750.vg
vg0_00003-1050448537.vg  vg0_00008-577028682.vg
vg0_00004-1537549129.vg  vg0_00009-1035978808.vg

La commande vgcfgbackup est utilisée pour sauvegarder les métadonnées manuellement dans le fichier /etc/lvm/backup/nom_du_volume_group :

La commande vgcfgrestore permet de restaurer une sauvegarde. Sans l'option -f pour spécifier la sauvegarde à restaurer, cette commande renvoie la liste des sauvegardes disponibles :

SUSE12SP1:~ # vgcfgbackup vg0
  Volume group "vg0" successfully backed up.

Il est aussi possible de modifier l'emplacement de la sauvegarde avec l'option -f de la commande :

SUSE12SP1:~ # vgcfgbackup -f /tmp/vg0_backup vg0
  Volume group "vg0" successfully backed up.

SUSE12SP1:~ # vgcfgrestore --list vg0
   
  File:		/etc/lvm/archive/vg0_00000-1490864187.vg
  Couldn't find device with uuid SdDEnc-2fiL-IY82-K0zp-MSCx-w1Nj-zefWFA.
  Couldn't find device with uuid lnUsag-cM0o-76LP-PffQ-wJQK-0NKa-vjtFzy.
  Couldn't find device with uuid fO06lr-O2qe-ccmx-4JV6-98zm-CGBr-EWQUho.
  VG name:    	vg0
  Description:	Created *before* executing 'vgcreate -s 8M vg0 /dev/sdb2 /dev/sdb3 /dev/sdb6'
  Backup Time:	Tue Oct 10 16:31:14 2017

   
  File:		/etc/lvm/archive/vg0_00001-1258721014.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvcreate -L 350 -n lv0 vg0'
  Backup Time:	Tue Oct 10 16:34:48 2017

   
  File:		/etc/lvm/archive/vg0_00002-1552831049.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvextend -L +100M /dev/vg0/lv0'
  Backup Time:	Tue Oct 10 16:44:21 2017

   
  File:		/etc/lvm/archive/vg0_00003-1050448537.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvcreate -s -L 15M -n testsnap /dev/vg0/lv0'
  Backup Time:	Tue Oct 10 17:09:48 2017

   
  File:		/etc/lvm/archive/vg0_00004-1537549129.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvremove /dev/vg0/testsnap'
  Backup Time:	Wed Oct 11 09:45:08 2017

   
  File:		/etc/lvm/archive/vg0_00005-1861990860.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvremove /dev/vg0/lv0'
  Backup Time:	Wed Oct 11 09:45:41 2017

   
  File:		/etc/lvm/archive/vg0_00006-475023216.vg
  VG name:    	vg0
  Description:	Created *before* executing 'vgremove vg0'
  Backup Time:	Wed Oct 11 09:46:42 2017

   
  File:		/etc/lvm/archive/vg0_00007-1421103332.vg
  Couldn't find device with uuid 408GSr-a47G-cjbB-Vrpd-OfXs-pqZs-l0A7pW.
  Couldn't find device with uuid YU3YJD-s1nB-wAYz-e329-UcgK-je8c-aXwngf.
  Couldn't find device with uuid QgKnsv-ZW3O-YEaw-LNfY-ZyTt-WXHw-D8StdG.
  VG name:    	vg0
  Description:	Created *before* executing 'vgcreate -s 8M vg0 /dev/sdb2 /dev/sdb3 /dev/sdb6'
  Backup Time:	Wed Oct 11 09:49:08 2017

   
  File:		/etc/lvm/archive/vg0_00008-577028682.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvcreate -m 1 -L 100M -n lv1 vg0'
  Backup Time:	Wed Oct 11 09:49:30 2017

   
  File:		/etc/lvm/archive/vg0_00009-1035978808.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvconvert -m 0 /dev/vg0/lv1 /dev/sdb3'
  Backup Time:	Wed Oct 11 09:51:45 2017

   
  File:		/etc/lvm/archive/vg0_00010-1593394958.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvconvert -m 1 /dev/vg0/lv1'
  Backup Time:	Wed Oct 11 09:52:14 2017

   
  File:		/etc/lvm/archive/vg0_00011-1525730672.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvconvert -m 0 /dev/vg0/lv1 /dev/sdb3'
  Backup Time:	Wed Oct 11 09:52:18 2017

   
  File:		/etc/lvm/archive/vg0_00012-1449042750.vg
  VG name:    	vg0
  Description:	Created *before* executing 'lvcreate -i2 -I64 -n lv2 -L 100M vg0 /dev/sdb3 /dev/sdb6'
  Backup Time:	Wed Oct 11 09:59:20 2017

   
  File:		/etc/lvm/backup/vg0
  VG name:    	vg0
  Description:	Created *after* executing 'vgcfgbackup vg0'
  Backup Time:	Wed Oct 11 10:01:43 2017

Un journal est la partie d'un système de fichiers journalisé qui trace les opérations d'écriture tant qu'elles ne sont pas terminées et cela en vue de garantir l'intégrité des données en cas d'arrêt brutal.

L'intérêt est de pouvoir plus facilement et plus rapidement récupérer les données en cas d'arrêt brutal du système d'exploitation (coupure d'alimentation, plantage du système, etc.), alors que les partitions n'ont pas été correctement synchronisées et démontées.

Sans un tel fichier journal, un outil de récupération de données après un arrêt brutal doit parcourir l'intégralité du système de fichier pour vérifier sa cohérence. Lorsque la taille du système de fichiers est importante, cela peut durer très longtemps pour un résultat moins efficace car entraînant des pertes de données.

Linux peut utiliser un des systèmes de fichiers journalisés suivants :

Ext3 est une évolution de Ext2 et a pour principale différence d'utiliser un fichier journal. Il peut :

• être utilisé à partir d'une partition Ext2, sans avoir à sauvegarder et à restaurer des données,
• utiliser tous les utilitaires de maintenance pour les systèmes de fichiers ext2, comme fsck,
• utiliser le logiciel dump, ce qui n'est pas le cas avec ReiserFS.

Pour plus d'information concernant Ext3, consultez cette page

Notez maintenant le numéro de la dernière partition que vous avez précédemment créée :

SUSE12SP1:~ # fdisk -l

Disk /dev/sdb: 8 GiB, 8589934592 bytes, 16777216 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x31bcc5e2

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sdb1          2048  1026047  1024000  500M fd Linux raid autodetect
/dev/sdb2       1026048  1435647   409600  200M 8e Linux LVM
/dev/sdb3       1435648  2050047   614400  300M 8e Linux LVM
/dev/sdb4       2050048 16777215 14727168    7G  5 Extended
/dev/sdb5       2052096  3076095  1024000  500M fd Linux raid autodetect
/dev/sdb6       3078144  3897343   819200  400M 8e Linux LVM
/dev/sdb7       3899392  4923391  1024000  500M fd Linux raid autodetect
/dev/sdb8       4925440  5949439  1024000  500M fd Linux raid autodetect
/dev/sdb9       5951488  6361087   409600  200M 83 Linux

Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x000cd018

Device     Boot   Start      End  Sectors Size Id Type
/dev/sda1          2048  4208639  4206592   2G 82 Linux swap / Solaris
/dev/sda2  *    4208640 41943039 37734400  18G 83 Linux

Disk /dev/mapper/vg0-lv1: 104 MiB, 109051904 bytes, 212992 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk /dev/mapper/vg0-lv2: 112 MiB, 117440512 bytes, 229376 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 65536 bytes / 131072 bytes

Dans notre cas, il s'agit de /dev/sdb9.

Créez un filesystem Ext3 sur /dev/sdb9 en utilisant la commande mke2fs -j :

SUSE12SP1:~ # mke2fs -j /dev/sdb9
mke2fs 1.42.11 (09-Jul-2014)
Creating filesystem with 204800 1k blocks and 51200 inodes
Filesystem UUID: edad27da-4d67-40fb-af9b-d1bace3d1733
Superblock backups stored on blocks: 
	8193, 24577, 40961, 57345, 73729

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done 

Les options de la commande mke2fs sont :

SUSE12SP1:~ # mke2fs --help
mke2fs: invalid option -- '-'
Usage: mke2fs [-c|-l filename] [-b block-size] [-C cluster-size]
	[-i bytes-per-inode] [-I inode-size] [-J journal-options]
	[-G flex-group-size] [-N number-of-inodes]
	[-m reserved-blocks-percentage] [-o creator-os]
	[-g blocks-per-group] [-L volume-label] [-M last-mounted-directory]
	[-O feature[,...]] [-r fs-revision] [-E extended-option[,...]]
	[-t fs-type] [-T usage-type ] [-U UUID] [-jnqvDFKSV] device [blocks-count]

Pour vérifier si un système de fichiers Ext2 est journalisé, utilisez la commande dumpe2fs :

SUSE12SP1:~ # dumpe2fs -h /dev/sdb9
dumpe2fs 1.42.11 (09-Jul-2014)
Filesystem volume name:   <none>
Last mounted on:          <not available>
Filesystem UUID:          edad27da-4d67-40fb-af9b-d1bace3d1733
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      has_journal ext_attr resize_inode dir_index filetype sparse_super
Filesystem flags:         signed_directory_hash 
Default mount options:    user_xattr acl
Filesystem state:         clean
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              51200
Block count:              204800
Reserved block count:     10240
Free blocks:              192674
Free inodes:              51189
First block:              1
Block size:               1024
Fragment size:            1024
Reserved GDT blocks:      256
Blocks per group:         8192
Fragments per group:      8192
Inodes per group:         2048
Inode blocks per group:   256
Filesystem created:       Wed Oct 11 12:52:09 2017
Last mount time:          n/a
Last write time:          Wed Oct 11 12:52:09 2017
Mount count:              0
Maximum mount count:      -1
Last checked:             Wed Oct 11 12:52:09 2017
Check interval:           0 (<none>)
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)
First inode:              11
Inode size:	          128
Journal inode:            8
Default directory hash:   half_md4
Directory Hash Seed:      020741aa-ed55-4a18-b403-9605d7c95051
Journal backup:           inode blocks
Journal features:         (none)
Journal size:             4113k
Journal length:           4096
Journal sequence:         0x00000001
Journal start:            0

Les options de cette commande sont :

SUSE12SP1:~ # dumpe2fs --help
dumpe2fs 1.42.11 (09-Jul-2014)
dumpe2fs: invalid option -- '-'
Usage: dumpe2fs [-bfhixV] [-o superblock=<num>] [-o blocksize=<num>] device

Pour supprimer Ext3 sur cette partition, il convient d'utiliser la commande tune2fs

SUSE12SP1:~ # tune2fs -O ^has_journal /dev/sdb9
tune2fs 1.42.11 (09-Jul-2014)

Les options de cette commande sont :

SUSE12SP1:~ # tune2fs --help
tune2fs 1.42.11 (09-Jul-2014)
tune2fs: invalid option -- '-'
Usage: tune2fs [-c max_mounts_count] [-e errors_behavior] [-g group]
	[-i interval[d|m|w]] [-j] [-J journal_options] [-l]
	[-m reserved_blocks_percent] [-o [^]mount_options[,...]] [-p mmp_update_interval]
	[-r reserved_blocks_count] [-u user] [-C mount_count] [-L volume_label]
	[-M last_mounted_dir] [-O [^]feature[,...]]
	[-E extended-option[,...]] [-T last_check_time] [-U UUID]
	[ -I new_inode_size ] device

Constatez le résultat de cette commande :

SUSE12SP1:~ # dumpe2fs -h /dev/sdb9
dumpe2fs 1.42.11 (09-Jul-2014)
Filesystem volume name:   <none>
Last mounted on:          <not available>
Filesystem UUID:          edad27da-4d67-40fb-af9b-d1bace3d1733
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      ext_attr resize_inode dir_index filetype sparse_super
Filesystem flags:         signed_directory_hash 
Default mount options:    user_xattr acl
Filesystem state:         clean
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              51200
Block count:              204800
Reserved block count:     10240
Free blocks:              196787
Free inodes:              51189
First block:              1
Block size:               1024
Fragment size:            1024
Reserved GDT blocks:      256
Blocks per group:         8192
Fragments per group:      8192
Inodes per group:         2048
Inode blocks per group:   256
Filesystem created:       Wed Oct 11 12:52:09 2017
Last mount time:          n/a
Last write time:          Wed Oct 11 12:55:10 2017
Mount count:              0
Maximum mount count:      -1
Last checked:             Wed Oct 11 12:52:09 2017
Check interval:           0 (<none>)
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)
First inode:              11
Inode size:	          128
Default directory hash:   half_md4
Directory Hash Seed:      020741aa-ed55-4a18-b403-9605d7c95051
Journal backup:           inode blocks

Supprimez maintenant l'inode du journal :

SUSE12SP1:~ # fsck /dev/sdb9
fsck from util-linux 2.25
e2fsck 1.42.11 (09-Jul-2014)
/dev/sdb9: clean, 11/51200 files, 8013/204800 blocks

Créez un point de montage pour /dev/sdb9 :

SUSE12SP1:~ # mkdir /mnt/sdb9

Essayez de monter /dev/sdb9 en tant que système de fichiers Ext3. Vous obtiendrez un résultat similaire à celui-ci :

SUSE12SP1:~ # mount -t ext3 /dev/sdb9 /mnt/sdb9
mount: wrong fs type, bad option, bad superblock on /dev/sdb9,
       missing codepage or helper program, or other error

       In some cases useful info is found in syslog - try
       dmesg | tail or so.

Montez maintenant le système de fichiers en tant que Ext2 :

SUSE12SP1:~ # mount -t ext2 /dev/sdb9 /mnt/sdb9
SUSE12SP1:~ # 

Pour replacer le journal sur /dev/sdb9, il convient d'utiliser la commande tune2fs :

SUSE12SP1:~ # umount /mnt/sdb9
SUSE12SP1:~ # 
SUSE12SP1:~ # tune2fs -j /dev/sdb9
tune2fs 1.42.11 (09-Jul-2014)
Creating journal inode: done

Le journal d'un système de fichiers peut être placé sur un autre périphérique bloc.

Créez un système de fichiers sur /dev/sdb8 :

SUSE12SP1:~ # mke2fs -O journal_dev /dev/sdb8
mke2fs 1.42.11 (09-Jul-2014)
Creating filesystem with 512000 1k blocks and 0 inodes
Filesystem UUID: 9056ef8b-ceed-4e54-91cb-0d292742b803
Superblock backups stored on blocks: 

Zeroing journal device: SUSE12SP1:~ #  

Créez maintenant un système de fichiers Ext3 sur /dev/sdb9 en plaçant le journal sur /dev/sdb8 :

SUSE12SP1:~ # mke2fs -j -J device=/dev/sdb8 /dev/sdb9
mke2fs 1.42.11 (09-Jul-2014)
Using journal device's blocksize: 1024
/dev/sdb9 contains a ext3 file system
	last mounted on Wed Oct 11 13:31:57 2017
Proceed anyway? (y,n) y
Creating filesystem with 204800 1k blocks and 51200 inodes
Filesystem UUID: 2eb54210-df3c-4257-9764-2f6e8c4c1b33
Superblock backups stored on blocks: 
	8193, 24577, 40961, 57345, 73729

Allocating group tables: done                            
Writing inode tables: done                            
Adding journal to device /dev/sdb8: done
Writing superblocks and filesystem accounting information: done 

Pour modifiez la fréquence de vérification du système de fichiers sur /dev/sdb9, il convient d'utiliser soit l'option -c, soit l'option -i :

SUSE12SP1:~ # tune2fs -i 100d /dev/sdb9
tune2fs 1.42.11 (09-Jul-2014)
Setting interval between checks to 8640000 seconds

Dernièrement, pour obtenir seul l'UUID du système de fichiers, utilisez les commandes dumpe2fs et grep :

SUSE12SP1:~ # dumpe2fs /dev/sdb9 | grep UUID
dumpe2fs 1.42.11 (09-Jul-2014)
Filesystem UUID:          2eb54210-df3c-4257-9764-2f6e8c4c1b33
Journal UUID:             9056ef8b-ceed-4e54-91cb-0d292742b803

Le système de fichiers Ext4 fut introduit dans le noyau 2.6.19 en mode expérimental et est devenu stable dans le noyau 2.6.28.

Ext4 n'est pas une évolution de Ext3. Cependant il a une compatibilité ascendante avec Ext3.

Les fonctionnalités majeures d'Ext4 sont :

• la gestion des volumes d'une taille allant jusqu'à 1 024 pébioctets,
• l'allocation par extents qui permettent la pré-allocation d'une zone contiguë pour un fichier afin de minimiser la fragmentation.

L'option extents est activée par défaut depuis le noyau 2.6.23.

La compatibilité ascendante avec ext3 comprend :

• la possibilité de monter une partition Ext3 en tant que partition Ext4,
• la possibilité de monter une partition Ext4 en tant que partition Ext3 mais uniquement dans le cas où la partition Ext4 n'ait jamais utilisé l'allocation par extents pour enregistrer des fichiers, mais l'allocation binaire comprise par ext3.

Pour plus d'informations concernant Ext4, consultez cette page.

Créez un système de fichiers Ext4 sur /dev/sdb8 :

SUSE12SP1:~ # mkfs.ext4 /dev/sdb8
mke2fs 1.42.11 (09-Jul-2014)
/dev/sdb8 contains a jbd file system
Proceed anyway? (y,n) y
Creating filesystem with 512000 1k blocks and 128016 inodes
Filesystem UUID: ab2093f4-4e46-44cd-b73c-37a6e3d7849b
Superblock backups stored on blocks: 
	8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done

Les options de cette commande sont :

SUSE12SP1:~ # mkfs.ext4 --help
mkfs.ext4: invalid option -- '-'
Usage: mkfs.ext4 [-c|-l filename] [-b block-size] [-C cluster-size]
	[-i bytes-per-inode] [-I inode-size] [-J journal-options]
	[-G flex-group-size] [-N number-of-inodes]
	[-m reserved-blocks-percentage] [-o creator-os]
	[-g blocks-per-group] [-L volume-label] [-M last-mounted-directory]
	[-O feature[,...]] [-r fs-revision] [-E extended-option[,...]]
	[-t fs-type] [-T usage-type ] [-U UUID] [-jnqvDFKSV] device [blocks-count]

Consultez maintenant les caractéristiques du système de fichier :

SUSE12SP1:~ # dumpe2fs /dev/sdb8 | more
dumpe2fs 1.42.11 (09-Jul-2014)
Filesystem volume name:   <none>
Last mounted on:          <not available>
Filesystem UUID:          ab2093f4-4e46-44cd-b73c-37a6e3d7849b
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      has_journal ext_attr resize_inode dir_index filetype extent flex_bg sparse_super huge_file uninit_bg dir_nlink extra_isize
Filesystem flags:         signed_directory_hash 
Default mount options:    user_xattr acl
Filesystem state:         clean
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              128016
Block count:              512000
Reserved block count:     25600
Free blocks:              485334
Free inodes:              128005
First block:              1
Block size:               1024
Fragment size:            1024
Reserved GDT blocks:      256
Blocks per group:         8192
Fragments per group:      8192
Inodes per group:         2032
Inode blocks per group:   254
Flex block group size:    16
Filesystem created:       Wed Oct 11 13:42:38 2017
Last mount time:          n/a
Last write time:          Wed Oct 11 13:42:38 2017
Mount count:              0
Maximum mount count:      -1
Last checked:             Wed Oct 11 13:42:38 2017
Check interval:           0 (<none>)
--More--

Utilisez la commande e2label pour associer une étiquette au système de fichiers :

r
SUSE12SP1:~ # e2label /dev/sdb8 my_ext4
SUSE12SP1:~ # dumpe2fs /dev/sdb8 | grep volume
dumpe2fs 1.42.11 (09-Jul-2014)
Filesystem volume name:   my_ext4

Créez un point de montage dans /mnt et essayez de monter /dev/sdb8 en tant qu'Ext3 :

SUSE12SP1:~ # mkdir /mnt/sdb8
SUSE12SP1:~ # 
SUSE12SP1:~ # mount -t ext3 /dev/sdb8 /mnt/sdb8
mount: wrong fs type, bad option, bad superblock on /dev/sdb8,
       missing codepage or helper program, or other error

       In some cases useful info is found in syslog - try
       dmesg | tail or so.

Montez de nouveau la partition sans stipuler le type de système de fichiers :

SUSE12SP1:~ # mount /dev/sdb8 /mnt/sdb8
SUSE12SP1:~ # 
SUSE12SP1:~ # mount | grep sdb8
/dev/sdb8 on /mnt/sdb8 type ext4 (rw,relatime,data=ordered)

Créez un système de fichiers ext3 sur /dev/sdb9 :

SUSE12SP1:~ # mkfs.ext3 /dev/sdb9
mke2fs 1.42.11 (09-Jul-2014)
/dev/sdb9 contains a ext3 file system
	created on Wed Oct 11 13:40:14 2017
Proceed anyway? (y,n) y
Creating filesystem with 204800 1k blocks and 51200 inodes
Filesystem UUID: 299b24aa-d708-4934-b7c6-5741c49374c4
Superblock backups stored on blocks: 
	8193, 24577, 40961, 57345, 73729

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done 

Montez maintenant /dev/sdb9 sur /mnt/sdb9 :

SUSE12SP1:~ # mount /dev/sdb9 /mnt/sdb9
SUSE12SP1:~ # ls -l /mnt/sdb9
total 12
drwx------ 2 root root 12288 Oct 11 13:48 lost+found

Créez le fichier /mnt/sdb9/check_file :

SUSE12SP1:~ # touch /mnt/sdb9/check_file

Injectez la chaine check file dans le fichier /mnt/sdb9/check_file puis démontez /dev/sdb9 :

SUSE12SP1:~ # echo "check file" > /mnt/sdb9/check_file
SUSE12SP1:~ # 
SUSE12SP1:~ # umount /dev/sdb9

Exécutez e2fsck sur /dev/sdb9 :

SUSE12SP1:~ # e2fsck /dev/sdb9
e2fsck 1.42.11 (09-Jul-2014)
/dev/sdb9: clean, 12/51200 files, 12127/204800 blocks

Convertissez /dev/sdb9 en Ext4 :

SUSE12SP1:~ # tune2fs -O extents,uninit_bg,dir_index /dev/sdb9
tune2fs 1.42.11 (09-Jul-2014)

Optimisez le système de fichiers :

SUSE12SP1:~ # e2fsck -fDC0 /dev/sdb9
e2fsck 1.42.11 (09-Jul-2014)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure                                           
Pass 3: Checking directory connectivity
Pass 3A: Optimizing directories
Pass 4: Checking reference counts
Pass 5: Checking group summary information
                                                                               
/dev/sdb9: ***** FILE SYSTEM WAS MODIFIED *****
/dev/sdb9: 12/51200 files (0.0% non-contiguous), 12127/204800 blocks

Essayez de monter /dev/sdb9 en tant qu'Ext3 :

SUSE12SP1:~ # mount -t ext3 /dev/sdb9 /mnt/sdb9
mount: wrong fs type, bad option, bad superblock on /dev/sdb9,
       missing codepage or helper program, or other error

       In some cases useful info is found in syslog - try
       dmesg | tail or so.

Montez /dev/sdb9 sans spécifier le type de fichiers Ext3 et vérifiez le contenu du fichier check_file :

SUSE12SP1:~ # mount /dev/sdb9 /mnt/sdb9
SUSE12SP1:~ # 
SUSE12SP1:~ # ls -l /mnt/sdb9
total 13
-rw-r--r-- 1 root root    11 Oct 11 13:51 check_file
drwx------ 2 root root 12288 Oct 11 13:48 lost+found
SUSE12SP1:~ # 
SUSE12SP1:~ # cat /mnt/sdb9/check_file
check file

Dernièrement, pour obtenir seul l'UUID du système de fichiers, utilisez les commandes dumpe2fs et grep :

SUSE12SP1:~ # dumpe2fs /dev/sdb8 | grep UUID
dumpe2fs 1.42.11 (09-Jul-2014)
Filesystem UUID:          ab2093f4-4e46-44cd-b73c-37a6e3d7849b
SUSE12SP1:~ # dumpe2fs /dev/sdb9 | grep UUID
dumpe2fs 1.42.11 (09-Jul-2014)
Filesystem UUID:          299b24aa-d708-4934-b7c6-5741c49374c4

XFS est un système de fichiers 64-bit journalisé de haute performance crée par SGI pour son système d'exploitation IRIX. XFS est inclus par défaut avec les versions du noyau Linux 2.5.xx et 2.6.xx.

Debian propose aussi une version 32 bits du système de fichiers XFS.

Pour plus d'informations concernant XFS, consultez cette page.

Démontez /dev/sdb9 :

SUSE12SP1:~ # umount /dev/sdb9

Créez un système de fichiers XFS sur la partition /dev/sdb9 :

SUSE12SP1:~ # mkfs.xfs /dev/sdb9
mkfs.xfs: /dev/sdb9 appears to contain an existing filesystem (ext4).
mkfs.xfs: Use the -f option to force overwrite.
SUSE12SP1:~ # mkfs.xfs -f /dev/sdb9
meta-data=/dev/sdb9              isize=256    agcount=4, agsize=12800 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0        finobt=0
data     =                       bsize=4096   blocks=51200, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=0
log      =internal log           bsize=4096   blocks=853, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

Les options de cette commande sont :

SUSE12SP1:~ # mkfs.xfs --help
mkfs.xfs: invalid option -- '-'
unknown option -- 
Usage: mkfs.xfs
/* blocksize */		[-b log=n|size=num]
/* metadata */		[-m crc=0|1,finobt=0|1]
/* data subvol */	[-d agcount=n,agsize=n,file,name=xxx,size=num,
			    (sunit=value,swidth=value|su=num,sw=num|noalign),
			    sectlog=n|sectsize=num
/* force overwrite */	[-f]
/* inode size */	[-i log=n|perblock=n|size=num,maxpct=n,attr=0|1|2,
			    projid32bit=0|1]
/* no discard */	[-K]
/* log subvol */	[-l agnum=n,internal,size=num,logdev=xxx,version=n
			    sunit=value|su=num,sectlog=n|sectsize=num,
			    lazy-count=0|1]
/* label */		[-L label (maximum 12 characters)]
/* naming */		[-n log=n|size=num,version=2|ci,ftype=0|1]
/* no-op info only */	[-N]
/* prototype file */	[-p fname]
/* quiet */		[-q]
/* realtime subvol */	[-r extsize=num,size=num,rtdev=xxx]
/* sectorsize */	[-s log=n|size=num]
/* version */		[-V]
			devicename
<devicename> is required unless -d name=xxx is given.
<num> is xxx (bytes), xxxs (sectors), xxxb (fs blocks), xxxk (xxx KiB),
      xxxm (xxx MiB), xxxg (xxx GiB), xxxt (xxx TiB) or xxxp (xxx PiB).
<value> is xxx (512 byte blocks).

Consultez maintenant les caractéristiques du système de fichier :

SUSE12SP1:~ # xfs_info /dev/sdb9
xfs_info: /dev/sdb9 is not a mounted XFS filesystem
SUSE12SP1:~ # mount /dev/sdb9 /mnt/sdb9
SUSE12SP1:~ # xfs_info /dev/sdb9
meta-data=/dev/sdb9              isize=256    agcount=4, agsize=12800 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0        finobt=0
data     =                       bsize=4096   blocks=51200, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=0
log      =internal               bsize=4096   blocks=853, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

Les options de cette commande sont :

SUSE12SP1:~ # xfs_info --help
/usr/sbin/xfs_info: illegal option -- -
Usage: xfs_info [-V] [-t mtab] mountpoint

Utilisez la commande xfs_admin pour associer une étiquette au système de fichiers :

SUSE12SP1:~ # xfs_admin -L my_xfs /dev/sdb9
xfs_admin: /dev/sdb9 contains a mounted filesystem

fatal error -- couldn't initialize XFS library

SUSE12SP1:~ # umount /dev/sdb9

SUSE12SP1:~ # xfs_admin -L my_xfs /dev/sdb9
writing all SBs
new label = "my_xfs"

Pour voir l'étiquette, utilisez la commande suivante :

SUSE12SP1:~ # xfs_admin -l /dev/sdb9
label = "my_xfs"

Les options de cette commande sont :

SUSE12SP1:~ # xfs_admin --help
/usr/sbin/xfs_admin: illegal option -- -
Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-U uuid] device

Dernièrement, pour obtenir seul l'UUID du système de fichiers, utilisez la commande xfs-admin et l'option -u :

SUSE12SP1:~ # xfs_admin -u /dev/sdb9
UUID = 88690d3d-c6de-4b81-88ec-cff03a1de984

ReiserFS permet :

• de meilleurs temps d'accès à des sous-répertoires que Ext3, même ceux contenant des dizaines de milliers de fichiers,
• une plus grande efficacité pour ce qui concerne le stockage des fichiers moins de quelques ko. Le gain d'espace peut aller jusqu'à 10% par rapport à Ext2/Ext3.

Pour plus d'informations concernant ReiserFS, consultez cette page.

Créez un système de fichiers ReiserFS sur la partition /dev/sda9 :

SUSE12SP1:~ # mkfs.reiserfs /dev/sdb7
mkfs.reiserfs 3.6.24

Guessing about desired format.. Kernel 3.12.74-60.64.40-default is running.
Format 3.6 with standard journal
Count of blocks on the device: 128000
Number of blocks consumed by mkreiserfs formatting process: 8215
Blocksize: 4096
Hash function used to sort names: "r5"
Journal Size 8193 blocks (first block 18)
Journal Max transaction length 1024
inode generation number: 0
UUID: 0d6ce4b9-9b35-4fa5-8b77-43a058b0704b
ATTENTION: YOU SHOULD REBOOT AFTER FDISK!
	ALL DATA WILL BE LOST ON '/dev/sdb7'!
Continue (y/n):y
Initializing journal - 0%....20%....40%....60%....80%....100%
Syncing..ok
ReiserFS is successfully created on /dev/sdb7.

Les options de cette commande sont :

SUSE12SP1:~ # mkfs.reiserfs --help
mkfs.reiserfs: unrecognized option '--help'
Usage: mkfs.reiserfs [options]  device [block-count]

Options:

  -b | --block-size N              size of file-system block, in bytes
  -j | --journal-device FILE       path to separate device to hold journal
  -s | --journal-size N            size of the journal in blocks
  -o | --journal-offset N          offset of the journal from the start of
                                   the separate device, in blocks
  -t | --transaction-max-size N    maximal size of transaction, in blocks
  -B | --badblocks file            store all bad blocks given in file on the fs
  -h | --hash rupasov|tea|r5       hash function to use by default
  -u | --uuid UUID                 store UUID in the superblock
  -l | --label LABEL               store LABEL in the superblock
  --format 3.5|3.6                 old 3.5 format or newer 3.6
  -f | --force                     specified once, make mkreiserfs the whole
                                   disk, not block device or mounted partition;
                                   specified twice, do not ask for confirmation
  -q | --quiet                     quiet work without messages, progress and
                                   questions. Useful if run in a script. For use
                                   by end users only.
  -d | --debug                     print debugging information during mkreiser
  -V                               print version and exit

Consultez maintenant les caractéristiques du système de fichier :

SUSE12SP1:~ # debugreiserfs /dev/sdb7
debugreiserfs 3.6.24


Filesystem state: consistent

Reiserfs super block in block 16 on 0x817 of format 3.6 with standard journal
Count of blocks on the device: 128000
Number of bitmaps: 4
Blocksize: 4096
Free blocks (count of blocks - used [journal, bitmaps, data, reserved] blocks): 119785
Root block: 8211
Filesystem is clean
Tree height: 2
Hash function used to sort names: "r5"
Objectid map size 2, max 972
Journal parameters:
	Device [0x0]
	Magic [0x40f9e556]
	Size 8193 blocks (including 1 for journal header) (first block 18)
	Max transaction length 1024 blocks
	Max batch size 900 blocks
	Max commit age 30
Blocks reserved by journal: 0
Fs state field: 0x0:
sb_version: 2
inode generation number: 0
UUID: 0d6ce4b9-9b35-4fa5-8b77-43a058b0704b
LABEL: 
Set flags in SB:
	ATTRIBUTES CLEAN
Mount count: 1
Maximum mount count: 30
Last fsck run: Wed Oct 11 15:48:41 2017
Check interval in days: 180

Les options de cette commande sont :

SUSE12SP1:~ # debugreiserfs --help
debugreiserfs: invalid option -- '-'
debugreiserfs: invalid option -- 'h'
debugreiserfs: invalid option -- 'e'
Usage: debugreiserfs [options] device

Options:
  -d		print blocks details of the internal tree
  -D		print blocks details of all used blocks
  -B file	extract list of badblocks
  -m		print bitmap blocks
  -o		print objectid map

  -J		print journal header
  -j filename
		print journal located on the device 'filename'
  		stores the journal in the specified file 'filename.
  -p		send filesystem metadata to stdout
  -u		read stdin and unpack the metadata
  -S		handle all blocks, not only used
  -1 block	block to print
  -q		no speed info
  -V		print version and exit

Utilisez la commande reiserfstune pour associer une étiquette au système de fichiers :

SUSE12SP1:~ # reiserfstune -l my_reiserfs /dev/sdb7
reiserfstune: Journal device has not been specified. Assuming journal is on the main device (/dev/sdb7).

Current parameters:

Filesystem state: consistent

Reiserfs super block in block 16 on 0x817 of format 3.6 with standard journal
Count of blocks on the device: 128000
Number of bitmaps: 4
Blocksize: 4096
Free blocks (count of blocks - used [journal, bitmaps, data, reserved] blocks): 119785
Root block: 8211
Filesystem is clean
Tree height: 2
Hash function used to sort names: "r5"
Objectid map size 2, max 972
Journal parameters:
	Device [0x0]
	Magic [0x40f9e556]
	Size 8193 blocks (including 1 for journal header) (first block 18)
	Max transaction length 1024 blocks
	Max batch size 900 blocks
	Max commit age 30
Blocks reserved by journal: 0
Fs state field: 0x0:
sb_version: 2
inode generation number: 0
UUID: 0d6ce4b9-9b35-4fa5-8b77-43a058b0704b
LABEL: my_reiserfs
Set flags in SB:
	ATTRIBUTES CLEAN
Mount count: 1
Maximum mount count: 30
Last fsck run: Wed Oct 11 15:48:41 2017
Check interval in days: 180

Les options de cette commande sont :

SUSE12SP1:~ # reiserfstune --help
reiserfstune: Usage: reiserfstune [options] device [block-count]

Options:

  -j | --journal-device file	current journal device
  --journal-new-device file	new journal device
  -o | --journal-new-offset N	new journal offset in blocks
  -s | --journal-new-size N	new journal size in blocks
  -t | --trans-max-size N	new journal max transaction size in blocks
  --no-journal-available	current journal is not available
  --make-journal-standard	new journal to be standard
  -b | --add-badblocks file	add to bad block list
  -B | --badblocks file		set the bad block list
  -u | --uuid UUID|random	set new UUID
  -l | --label LABEL		set new label
  -f | --force			force tuning, less confirmations
  -c | --check-interval		set interval in days for fsck -a to check,
                       		"disable" to disable check,
                       		or "default" to restore default
  -C | --time-last-checked	set the time the filesystem was last checked
                          	(now or YYYYMMDD[HH[MM[SS]]])
  -m | --max-mnt-count		set maximum number of mounts before fsck -a
                      		checks, "disable" to disable check,
                      		or "default" to restore default
  -M | --mnt-count		set the number of times the filesystem
                  		has been mounted
  -h | --help			print help and exit
  -V				print version and exit

Dernièrement, pour obtenir l'UUID du système de fichiers, utilisez les commandes debugreiserfs et grep :

SUSE12SP1:~ # debugreiserfs /dev/sdb7 | grep UUID
debugreiserfs 3.6.24

UUID: 0d6ce4b9-9b35-4fa5-8b77-43a058b0704b

JFS Journaled File System est un système de fichiers journalisé mis au point par IBM et disponible sous licence GPL.

Depuis la SLES 11-SP4, SUSE ne supporte plus JFS et a retiré tous les utilitaires de sa distribution.

Pour plus d'informations concernant JFS, consultez cette page.

Btrfs, (B-tree file system, prononcé ButterFS) est un système de fichiers expérimental basé sur la copie sur écriture sous licence GNU GPL, développé principalement par Oracle, Red Hat, Fujitsu, Intel, SUSE et STRATO AG, qui s'inspire grandement du système de fichiers ZFS utilisé par Solaris.

A noter sont les points suivants :

• Btrfs utilise des extents,
• Btrfs stocke les données des très petits fichiers directement dans l'extent du fichier répertoire, et non dans un extent séparé,
• Btrfs gère une notion de « sous-volumes » permettant ainsi des snapshots,
• Btrfs possède ses techniques propres de protection des données,
• Btrfs permet de redimensionner à chaud la taille du système de fichiers,
• Btrfs gère le RAID 0 ainsi que le RAID 1 logiciel,
• Btrfs gère la comprssion du système de fichiers.

Créez un système de fichiers Btrfs sur /dev/mapper/vg0-lv1 :

SUSE12SP1:~ # mkfs.btrfs /dev/mapper/vg0-lv1
SMALL VOLUME: forcing mixed metadata/data groups
btrfs-progs v4.1.2+20151002
See http://btrfs.wiki.kernel.org for more information.

Label:              (null)
UUID:               43e97638-f309-4769-a47a-b5d557f361f8
Node size:          4096
Sector size:        4096
Filesystem size:    104.00MiB
Block group profiles:
  Data+Metadata:    single            8.00MiB
  System:           single            4.00MiB
SSD detected:       no
Incompat features:  mixed-bg, extref, skinny-metadata
Number of devices:  1
Devices:
   ID        SIZE  PATH
    1   104.00MiB  /dev/mapper/vg0-lv1

Les options de cette commande sont :

SUSE12SP1:~ # mkfs.btrfs --help
usage: mkfs.btrfs [options] dev [ dev ... ]
options:
	-A|--alloc-start START  the offset to start the FS
	-b|--byte-count SIZE    total number of bytes in the FS
	-d|--data PROFILE       data profile, raid0, raid1, raid5, raid6, raid10, dup or single
	-f|--force              force overwrite of existing filesystem
	-l|--leafsize SIZE      deprecated, alias for nodesize
	-L|--label LABEL        set a label
	-m|--metadata PROFILE   metadata profile, values like data profile
	-M|--mixed              mix metadata and data together
	-n|--nodesize SIZE      size of btree nodes
	-s|--sectorsize SIZE    min block allocation (may not mountable by current kernel)
	-r|--rootdir DIR        the source directory
	-K|--nodiscard          do not perform whole device TRIM
	-O|--features LIST      comma separated list of filesystem features, use '-O list-all' to list features
	-U|--uuid UUID          specify the filesystem UUID
	-q|--quiet              no messages except errors
	-V|--version            print the mkfs.btrfs version and exit
btrfs-progs v4.1.2+20151002

Montez la partition btrfs sur /mnt :

SUSE12SP1:~ # mount -t btrfs /dev/vg0/lv1 /mnt/
SUSE12SP1:~ # mount | grep btrfs
/dev/sda2 on / type btrfs (rw,relatime,space_cache,subvolid=259,subvol=/@/.snapshots/1/snapshot)
/dev/sda2 on /.snapshots type btrfs (rw,relatime,space_cache,subvolid=258,subvol=/@/.snapshots)
/dev/sda2 on /var/spool type btrfs (rw,relatime,space_cache,subvolid=276,subvol=/@/var/spool)
/dev/sda2 on /var/opt type btrfs (rw,relatime,space_cache,subvolid=275,subvol=/@/var/opt)
/dev/sda2 on /var/lib/named type btrfs (rw,relatime,space_cache,subvolid=272,subvol=/@/var/lib/named)
/dev/sda2 on /var/lib/pgsql type btrfs (rw,relatime,space_cache,subvolid=273,subvol=/@/var/lib/pgsql)
/dev/sda2 on /var/tmp type btrfs (rw,relatime,space_cache,subvolid=277,subvol=/@/var/tmp)
/dev/sda2 on /var/lib/mariadb type btrfs (rw,relatime,space_cache,subvolid=270,subvol=/@/var/lib/mariadb)
/dev/sda2 on /var/lib/mysql type btrfs (rw,relatime,space_cache,subvolid=271,subvol=/@/var/lib/mysql)
/dev/sda2 on /var/lib/mailman type btrfs (rw,relatime,space_cache,subvolid=269,subvol=/@/var/lib/mailman)
/dev/sda2 on /usr/local type btrfs (rw,relatime,space_cache,subvolid=266,subvol=/@/usr/local)
/dev/sda2 on /var/crash type btrfs (rw,relatime,space_cache,subvolid=267,subvol=/@/var/crash)
/dev/sda2 on /var/lib/libvirt/images type btrfs (rw,relatime,space_cache,subvolid=268,subvol=/@/var/lib/libvirt/images)
/dev/sda2 on /tmp type btrfs (rw,relatime,space_cache,subvolid=265,subvol=/@/tmp)
/dev/sda2 on /opt type btrfs (rw,relatime,space_cache,subvolid=263,subvol=/@/opt)
/dev/sda2 on /srv type btrfs (rw,relatime,space_cache,subvolid=264,subvol=/@/srv)
/dev/sda2 on /boot/grub2/i386-pc type btrfs (rw,relatime,space_cache,subvolid=260,subvol=/@/boot/grub2/i386-pc)
/dev/sda2 on /boot/grub2/x86_64-efi type btrfs (rw,relatime,space_cache,subvolid=261,subvol=/@/boot/grub2/x86_64-efi)
/dev/sda2 on /home type btrfs (rw,relatime,space_cache,subvolid=262,subvol=/@/home)
/dev/sda2 on /var/log type btrfs (rw,relatime,space_cache,subvolid=274,subvol=/@/var/log)
/dev/mapper/vg0-lv1 on /mnt type btrfs (rw,relatime,space_cache,subvolid=5,subvol=/)

Sous Btrfs, il est possible de créer des sous volumes. Pour comprendre, comparez notre partition Btrfs à un VG et des sous volumes comme des LV :

SUSE12SP1:~ # btrfs subvolume create /mnt/volume1
Create subvolume '/mnt/volume1'
SUSE12SP1:~ # btrfs subvolume list /mnt/
ID 256 gen 6 top level 5 path volume1
SUSE12SP1:~ # ls -l /mnt
total 0
drwxr-xr-x 1 root root 0 Oct 11 16:08 volume1

Agrandisez le volume logique /dev/vg0/lv2 :

SUSE12SP1:~ # lvextend -L +600M /dev/vg0/lv2
  Using stripesize of last segment 64.00 KiB
  Rounding size (89 extents) up to stripe boundary size for segment (90 extents)
  Size of logical volume vg0/lv2 changed from 112.00 MiB (14 extents) to 720.00 MiB (90 extents).
  Logical volume lv2 successfully resized

Créez un système de fichiers Ext4 sur /dev/vg0/lv2 :

SUSE12SP1:~ # mkfs.ext4 /dev/vg0/lv2
mke2fs 1.42.11 (09-Jul-2014)
Creating filesystem with 184320 4k blocks and 46080 inodes
Filesystem UUID: 39528cf1-688e-4d72-a774-9a64039ab157
Superblock backups stored on blocks: 
	32768, 98304, 163840

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done

Convertissez maintenant le systèm de fichiers Ext4 en Btrfs :

SUSE12SP1:~ # btrfs-convert /dev/vg0/lv2
create btrfs filesystem:
	blocksize: 4096
	nodesize:  16384
	features:  extref, skinny-metadata (default)
creating btrfs metadata.
copy inodes [o] [         0/        11]
creating ext2 image file.
cleaning up system chunk.
conversion complete. 

Visualisez les systèmes de fichiers Btrfs :

SUSE12SP1:~ # btrfs filesystem show
Label: none  uuid: 65337196-2d6b-4c8b-b917-30c3867bf265
	Total devices 1 FS bytes used 5.94GiB
	devid    1 size 17.99GiB used 7.32GiB path /dev/sda2

Label: none  uuid: 43e97638-f309-4769-a47a-b5d557f361f8
	Total devices 1 FS bytes used 36.00KiB
	devid    1 size 104.00MiB used 12.00MiB path /dev/mapper/vg0-lv1

Label: none  uuid: 1d2c92a7-249c-4500-9dec-6c7bbc417401
	Total devices 1 FS bytes used 28.21MiB
	devid    1 size 720.00MiB used 720.00MiB path /dev/mapper/vg0-lv2

btrfs-progs v4.1.2+20151002

Ajouter la partition /dev/vg0/lv2 à /mnt :

SUSE12SP1:~ # btrfs device add /dev/vg0/lv2 /mnt/
/dev/vg0/lv2 appears to contain an existing filesystem (btrfs).
Use the -f option to force overwrite.
SUSE12SP1:~ # 
SUSE12SP1:~ # btrfs device add -f /dev/vg0/lv2 /mnt/
SUSE12SP1:~ #
SUSE12SP1:~ # btrfs filesystem show
Label: none  uuid: 65337196-2d6b-4c8b-b917-30c3867bf265
	Total devices 1 FS bytes used 5.94GiB
	devid    1 size 17.99GiB used 7.32GiB path /dev/sda2

Label: none  uuid: 43e97638-f309-4769-a47a-b5d557f361f8
	Total devices 2 FS bytes used 36.00KiB
	devid    1 size 104.00MiB used 12.00MiB path /dev/mapper/vg0-lv1
	devid    2 size 720.00MiB used 0.00B path /dev/mapper/vg0-lv2

btrfs-progs v4.1.2+20151002
SUSE12SP1:~ #
SUSE12SP1:~ # df -h
Filesystem           Size  Used Avail Use% Mounted on
/dev/sda2             18G  6.5G   12G  37% /
devtmpfs             815M  8.0K  815M   1% /dev
tmpfs                824M  144K  824M   1% /dev/shm
tmpfs                824M  9.7M  814M   2% /run
tmpfs                824M     0  824M   0% /sys/fs/cgroup
/dev/sda2             18G  6.5G   12G  37% /.snapshots
/dev/sda2             18G  6.5G   12G  37% /var/spool
/dev/sda2             18G  6.5G   12G  37% /var/opt
/dev/sda2             18G  6.5G   12G  37% /var/lib/named
/dev/sda2             18G  6.5G   12G  37% /var/lib/pgsql
/dev/sda2             18G  6.5G   12G  37% /var/tmp
/dev/sda2             18G  6.5G   12G  37% /var/lib/mariadb
/dev/sda2             18G  6.5G   12G  37% /var/lib/mysql
/dev/sda2             18G  6.5G   12G  37% /var/lib/mailman
/dev/sda2             18G  6.5G   12G  37% /usr/local
/dev/sda2             18G  6.5G   12G  37% /var/crash
/dev/sda2             18G  6.5G   12G  37% /var/lib/libvirt/images
/dev/sda2             18G  6.5G   12G  37% /tmp
/dev/sda2             18G  6.5G   12G  37% /opt
/dev/sda2             18G  6.5G   12G  37% /srv
/dev/sda2             18G  6.5G   12G  37% /boot/grub2/i386-pc
/dev/sda2             18G  6.5G   12G  37% /boot/grub2/x86_64-efi
/dev/sda2             18G  6.5G   12G  37% /home
/dev/sda2             18G  6.5G   12G  37% /var/log
/dev/mapper/vg0-lv1  824M  4.1M  819M   1% /mnt

Creéz un snapshot du volume /mnt :

SUSE12SP1:~ # btrfs subvolume snapshot /mnt /mnt/snapshot
Create a snapshot of '/mnt' in '/mnt/snapshot'
SUSE12SP1:~ # 
SUSE12SP1:~ # ls -l /mnt
total 4
drwxr-xr-x 1 root root 14 Oct 11 16:06 snapshot
drwxr-xr-x 1 root root  0 Oct 11 16:08 volume1

Démontez le système de fichiers btrfs :

SUSE12SP1:~ # umount /mnt

Montez ensuite le snapshot :

SUSE12SP1:~ # mount -o subvol=snapshot /dev/vg0/lv1 /mnt/
SUSE12SP1:~ # ls -l /mnt
total 0
drwxr-xr-x 1 root root 0 Oct 11 16:18 volume1

Pour voir les caractéristques du système de fichiers Btrfs, utilisez la commande suivante :

SUSE12SP1:~ # btrfs-show-super /dev/vg0/lv1
superblock: bytenr=65536, device=/dev/vg0/lv1
---------------------------------------------------------
csum			0xd2aa2507 [match]
bytenr			65536
flags			0x1
			( WRITTEN )
magic			_BHRfS_M [match]
fsid			43e97638-f309-4769-a47a-b5d557f361f8
label			
generation		11
root			4222976
sys_array_size		97
chunk_root_generation	8
root_level		1
chunk_root		135168
chunk_root_level	0
log_root		0
log_root_transid	0
log_root_level		0
total_bytes		864026624
bytes_used		49152
sectorsize		4096
nodesize		4096
leafsize		4096
stripesize		4096
root_dir		6
num_devices		2
compat_flags		0x0
compat_ro_flags		0x0
incompat_flags		0x145
			( MIXED_BACKREF |
			  MIXED_GROUPS |
			  EXTENDED_IREF |
			  SKINNY_METADATA )
csum_type		0
csum_size		4
cache_generation	11
uuid_tree_generation	11
dev_item.uuid		ebfacc21-4ce5-4708-8410-38dd8bed3160
dev_item.fsid		43e97638-f309-4769-a47a-b5d557f361f8 [match]
dev_item.type		0
dev_item.total_bytes	109051904
dev_item.bytes_used	12582912
dev_item.io_align	4096
dev_item.io_width	4096
dev_item.sector_size	4096
dev_item.devid		1
dev_item.dev_group	0
dev_item.seek_speed	0
dev_item.bandwidth	0
dev_item.generation	0

Créez un une etiquette avec la commande btrfs filesystem label :

SUSE12SP1:~ # btrfs filesystem label /mnt my_btrfs
SUSE12SP1:~ # btrfs-show-super /dev/vg0/lv1
superblock: bytenr=65536, device=/dev/vg0/lv1
---------------------------------------------------------
csum			0x88d0a74b [match]
bytenr			65536
flags			0x1
			( WRITTEN )
magic			_BHRfS_M [match]
fsid			43e97638-f309-4769-a47a-b5d557f361f8
label			my_btrfs
generation		12
root			4198400
sys_array_size		97
chunk_root_generation	8
root_level		1
chunk_root		135168
chunk_root_level	0
log_root		0
log_root_transid	0
log_root_level		0
total_bytes		864026624
bytes_used		49152
sectorsize		4096
nodesize		4096
leafsize		4096
stripesize		4096
root_dir		6
num_devices		2
compat_flags		0x0
compat_ro_flags		0x0
incompat_flags		0x145
			( MIXED_BACKREF |
			  MIXED_GROUPS |
			  EXTENDED_IREF |
			  SKINNY_METADATA )
csum_type		0
csum_size		4
cache_generation	12
uuid_tree_generation	12
dev_item.uuid		ebfacc21-4ce5-4708-8410-38dd8bed3160
dev_item.fsid		43e97638-f309-4769-a47a-b5d557f361f8 [match]
dev_item.type		0
dev_item.total_bytes	109051904
dev_item.bytes_used	12582912
dev_item.io_align	4096
dev_item.io_width	4096
dev_item.sector_size	4096
dev_item.devid		1
dev_item.dev_group	0
dev_item.seek_speed	0
dev_item.bandwidth	0
dev_item.generation	0

Pour créer un fichier ISO à partir d'une arborescence de fichiers, il convient d'utiliser la commande mkisofs :

SUSE12SP1:~ # cd /tmp
SUSE12SP1:/tmp # genisoimage -o tmp.iso /tmp
I: -input-charset not specified, using utf-8 (detected in locale settings)
Using _JAVA000.;1 for  /.java_pid8404 (.java_pid1671)
Using SYSTE000.SER for  /systemd-private-dc647e4673bf4bc9af99403caefb8c16-rtkit-daemon.service-k0MzkG (systemd-private-47979e849a3644dc81758975d6a508d4-rtkit-daemon.service-APKqKJ)
Using SYSTE001.SER for  /systemd-private-47979e849a3644dc81758975d6a508d4-rtkit-daemon.service-APKqKJ (systemd-private-fcfd6105e7604dc9a85456df8d37f40b-rtkit-daemon.service-9mcSak)
Using _JAVA001.;1 for  /.java_pid1671 (.java_pid1612)
Using _JAVA002.;1 for  /.java_pid1612 (.java_pid1690)
Using _JAVA003.;1 for  /.java_pid1690 (.java_pid1662)
Using _JAVA004.;1 for  /.java_pid1662 (.java_pid1532)
Using SYSTE002.SER for  /systemd-private-fcfd6105e7604dc9a85456df8d37f40b-rtkit-daemon.service-9mcSak (systemd-private-a9ca64d7289f4871b7c434cdad64e9b0-rtkit-daemon.service-bev5Nn)
Using _JAVA005.;1 for  /.java_pid1532 (.java_pid2392)
Using _JAVA006.;1 for  /.java_pid2392 (.java_pid3281)
Using MANAG000.;1 for  /managera1411267841657715235client (managera5050357016347721452server)
Using MANAG001.;1 for  /managera5050357016347721452server (managera4847938942232964844client)
Using MANAG002.;1 for  /managera4847938942232964844client (managera3336001029897679475server)
Using SYSTE003.SER for  /systemd-private-a9ca64d7289f4871b7c434cdad64e9b0-rtkit-daemon.service-bev5Nn (systemd-private-04f820fa26c745be8ddba814c6292f21-rtkit-daemon.service-o4lKP5)
Using RUN_C000.283;1 for  /tmp/run-crons.tGyimF/run-crons.daily.2832 (run-crons_output.2832)
Using RUN_C001.283;1 for  /tmp/run-crons.tGyimF/run-crons_output.2832 (run-crons_mail.2832)
Total translation table size: 0
Total rockridge attributes bytes: 0
Total directory bytes: 51200
Path table size(bytes): 414
Max brk space used 1a000
713 extents written (1 MB)

Le fichier ISO peut être monter en utilisant un périphérique de type loop :

SUSE12SP1:/tmp # mount tmp.iso /mnt -o loop
mount: /dev/loop0 is write-protected, mounting read-only
SUSE12SP1:/tmp # ls /mnt
_esd_100  _ice_uni  _java002  _java005  _test_un  _xim_uni  manag000  managera  repertoi      syste001.ser  systemd_.ser  tmp.iso
_esd_486  _java000  _java003  _java006  _x0_lock  hsperfda  manag001  mc_root   run_cron.tgy  syste002.ser  systemic      vboxgues.sym
_font_un  _java001  _java004  _java_pi  _x11_uni  inherit   manag002  public_d  syste000.ser  syste003.ser  systemic      vg0_back

Démontez maintenant le fichier ISO :

SUSE12SP1:/tmp # cd ~
SUSE12SP1:~ # umount /tmp/tmp.iso

Les options de cette commande sont :

SUSE12SP1:~ # genisoimage --help
Usage: genisoimage [options] file...
Options:
  -nobak                      Do not include backup files
  -no-bak                     Do not include backup files
  -abstract FILE              Set Abstract filename
  -A ID, -appid ID            Set Application ID
  -biblio FILE                Set Bibliographic filename
  -cache-inodes               Cache inodes (needed to detect hard links)
  -no-cache-inodes            Do not cache inodes (if filesystem has no unique unides)
  -check-oldnames             Check all imported ISO9660 names from old session
  -check-session FILE         Check all ISO9660 names from previous session
  -copyright FILE             Set Copyright filename
  -debug                      Set debug flag
  -b FILE, -eltorito-boot FILE
                              Set El Torito boot image name
  -eltorito-alt-boot          Start specifying alternative El Torito boot parameters
  -B FILES, -sparc-boot FILES Set sparc boot image names
  -sunx86-boot FILES          Set sunx86 boot image names
  -G FILE, -generic-boot FILE Set generic boot image name
  -sparc-label label text     Set sparc boot disk label
  -sunx86-label label text    Set sunx86 boot disk label
  -c FILE, -eltorito-catalog FILE
                              Set El Torito boot catalog name
  -C PARAMS, -cdrecord-params PARAMS
                              Magic paramters from cdrecord
  -d, -omit-period            Omit trailing periods from filenames (violates ISO9660)
  -dir-mode mode              Make the mode of all directories this mode.
  -D, -disable-deep-relocation
                              Disable deep directory relocation (violates ISO9660)
  -file-mode mode             Make the mode of all plain files this mode.
  -f, -follow-links           Follow symbolic links
  -gid gid                    Make the group owner of all files this gid.
  -graft-points               Allow to use graft points for filenames
  -root DIR                   Set root directory for all new files and directories
  -old-root DIR               Set root directory in previous session that is searched for files
  -help                       Print option help
  -hide GLOBFILE              Hide ISO9660/RR file
  -hide-list FILE             File with list of ISO9660/RR files to hide
  -hidden GLOBFILE            Set hidden attribute on ISO9660 file
  -hidden-list FILE           File with list of ISO9660 files with hidden attribute
  -hide-joliet GLOBFILE       Hide Joliet file
  -hide-joliet-list FILE      File with list of Joliet files to hide
  -hide-joliet-trans-tbl      Hide TRANS.TBL from Joliet tree
  -hide-rr-moved              Rename RR_MOVED to .rr_moved in Rock Ridge tree
  -gui                        Switch behaviour for GUI
  -i ADD_FILES                No longer supported
  -input-charset CHARSET      Local input charset for file name conversion
  -output-charset CHARSET     Output charset for file name conversion
  -iso-level LEVEL            Set ISO9660 conformance level (1..3) or 4 for ISO9660 version 2
  -J, -joliet                 Generate Joliet directory information
  -joliet-long                Allow Joliet file names to be 103 Unicode characters
  -jcharset CHARSET           Local charset for Joliet directory information
  -l, -full-iso9660-filenames Allow full 31 character filenames for ISO9660 names
  -max-iso9660-filenames      Allow 37 character filenames for ISO9660 names (violates ISO9660)
  -allow-limited-size         Allow different file sizes in ISO9660/UDF on large files
  -allow-leading-dots         Allow ISO9660 filenames to start with '.' (violates ISO9660)
  -ldots                      Allow ISO9660 filenames to start with '.' (violates ISO9660)
  -L, -allow-leading-dots     Allow ISO9660 filenames to start with '.' (violates ISO9660)
  -log-file LOG_FILE          Re-direct messages to LOG_FILE
  -m GLOBFILE, -exclude GLOBFILE
                              Exclude file name
  -exclude-list FILE          File with list of file names to exclude
  -pad                        Pad output to a multiple of 32k (default)
  -no-pad                     Do not pad output to a multiple of 32k
  -M FILE, -prev-session FILE Set path to previous session to merge
  -dev SCSIdev                Set path to previous session to merge
  -N, -omit-version-number    Omit version number from ISO9660 filename (violates ISO9660)
  -new-dir-mode mode          Mode used when creating new directories.
  -force-rr                   Inhibit automatic Rock Ridge detection for previous session
  -no-rr                      Inhibit reading of Rock Ridge attributes from previous session
  -no-split-symlink-components
                              Inhibit splitting symlink components
  -no-split-symlink-fields    Inhibit splitting symlink fields
  -o FILE, -output FILE       Set output file name
  -path-list FILE             File with list of pathnames to process
  -p PREP, -preparer PREP     Set Volume preparer
  -print-size                 Print estimated filesystem size and exit
  -publisher PUB              Set Volume publisher
  -P PUB, -publisher PUB      Set Volume publisher
  -quiet                      Run quietly
  -r, -rational-rock          Generate rationalized Rock Ridge directory information
  -R, -rock                   Generate Rock Ridge directory information
  -s TYPE, -sectype TYPE      Set output sector type to e.g. data/xa1/raw
  -alpha-boot FILE            Set alpha boot image name (relative to image root)
  -hppa-cmdline CMDLINE       Set hppa boot command line (relative to image root)
  -hppa-kernel-32 FILE        Set hppa 32-bit image name (relative to image root)
  -hppa-kernel-64 FILE        Set hppa 64-bit image name (relative to image root)
  -hppa-bootloader FILE       Set hppa boot loader file name (relative to image root)
  -hppa-ramdisk FILE          Set hppa ramdisk file name (relative to image root)
  -mips-boot FILE             Set mips boot image name (relative to image root)
  -mipsel-boot FILE           Set mipsel boot image name (relative to image root)
  -jigdo-jigdo FILE           Produce a jigdo .jigdo file as well as the .iso
  -jigdo-template FILE        Produce a jigdo .template file as well as the .iso
  -jigdo-min-file-size SIZE   Minimum size for a file to be listed in the jigdo file
  -jigdo-force-md5 PATTERN    Pattern(s) where files MUST match an externally-supplied MD5sum
  -jigdo-exclude PATTERN      Pattern(s) to exclude from the jigdo file
  -jigdo-map PATTERN1=PATTERN2
                              Pattern(s) to map paths (e.g. Debian=/mirror/debian)
  -md5-list FILE              File containing MD5 sums of the files that should be checked
  -jigdo-template-compress ALGORITHM
                              Choose to use gzip or bzip2 compression for template data; default is gzip
  -checksum_algorithm_iso alg1,alg2,...
                              Specify the checksum types desired for the output image
  -checksum_algorithm_template alg1,alg2,...
                              Specify the checksum types desired for the output jigdo template
  -sort FILE                  Sort file content locations according to rules in FILE
  -split-output               Split output into files of approx. 1GB size
  -stream-file-name FILE_NAME Set the stream file ISO9660 name (incl. version)
  -stream-media-size #        Set the size of your CD media in sectors
  -sysid ID                   Set System ID
  -T, -translation-table      Generate translation tables for systems that don't understand long filenames
  -table-name TABLE_NAME      Translation table file name
  -ucs-level LEVEL            Set Joliet UCS level (1..3)
  -udf                        Generate UDF file system
  -dvd-video                  Generate DVD-Video compliant UDF file system
  -uid uid                    Make the owner of all files this uid.
  -U, -untranslated-filenames Allow Untranslated filenames (for HPUX & AIX - violates ISO9660). Forces -l, -d, -N, -allow-leading-dots, -relaxed-filenames, -allow-lowercase, -allow-multidot
  -relaxed-filenames          Allow 7 bit ASCII except lower case characters (violates ISO9660)
  -no-iso-translate           Do not translate illegal ISO characters '~', '-' and '#' (violates ISO9660)
  -allow-lowercase            Allow lower case characters in addition to the current character set (violates ISO9660)
  -allow-multidot             Allow more than one dot in filenames (e.g. .tar.gz) (violates ISO9660)
  -use-fileversion LEVEL      Use file version # from filesystem
  -v, -verbose                Verbose
  -version                    Print the current version
  -V ID, -volid ID            Set Volume ID
  -volset ID                  Set Volume set ID
  -volset-size #              Set Volume set size
  -volset-seqno #             Set Volume set sequence number
  -x FILE, -old-exclude FILE  Exclude file name(depreciated)
  -hard-disk-boot             Boot image is a hard disk image
  -no-emul-boot               Boot image is 'no emulation' image
  -no-boot                    Boot image is not bootable
  -boot-load-seg #            Set load segment for boot image
  -boot-load-size #           Set numbers of load sectors
  -boot-info-table            Patch boot image with info table
  -XA                         Generate XA directory attruibutes
  -xa                         Generate rationalized XA directory attruibutes
  -z, -transparent-compression
                              Enable transparent compression of files
  -hfs-type TYPE              Set HFS default TYPE
  -hfs-creator CREATOR        Set HFS default CREATOR
  -g, -apple                  Add Apple ISO9660 extensions
  -h, -hfs                    Create ISO9660/HFS hybrid
  -map MAPPING_FILE           Map file extensions to HFS TYPE/CREATOR
  -H MAPPING_FILE, -map MAPPING_FILE
                              Map file extensions to HFS TYPE/CREATOR
  -magic FILE                 Magic file for HFS TYPE/CREATOR
  -probe                      Probe all files for Apple/Unix file types
  -mac-name                   Use Macintosh name for ISO9660/Joliet/RockRidge file name
  -no-mac-files               Do not look for Unix/Mac files (depreciated)
  -boot-hfs-file FILE         Set HFS boot image name
  -part                       Generate HFS partition table
  -cluster-size SIZE          Cluster size for PC Exchange Macintosh files
  -auto FILE                  Set HFS AutoStart file name
  -no-desktop                 Do not create the HFS (empty) Desktop files
  -hide-hfs GLOBFILE          Hide HFS file
  -hide-hfs-list FILE         List of HFS files to hide
  -hfs-volid HFS_VOLID        Volume name for the HFS partition
  -icon-position              Keep HFS icon position
  -root-info FILE             finderinfo for root folder
  -input-hfs-charset CHARSET  Local input charset for HFS file name conversion
  -output-hfs-charset CHARSET Output charset for HFS file name conversion
  -hfs-unlock                 Leave HFS Volume unlocked
  -hfs-bless FOLDER_NAME      Name of Folder to be blessed
  -hfs-parms PARAMETERS       Comma separated list of HFS parameters
  -prep-boot FILE             PReP boot image file -- up to 4 are allowed
  -chrp-boot                  Add CHRP boot header
  --cap                       Look for AUFS CAP Macintosh files
  --netatalk                  Look for NETATALK Macintosh files
  --double                    Look for AppleDouble Macintosh files
  --ethershare                Look for Helios EtherShare Macintosh files
  --exchange                  Look for PC Exchange Macintosh files
  --sgi                       Look for SGI Macintosh files
  --macbin                    Look for MacBinary Macintosh files
  --single                    Look for AppleSingle Macintosh files
  --ushare                    Look for IPT UShare Macintosh files
  --xinet                     Look for XINET Macintosh files
  --dave                      Look for DAVE Macintosh files
  --sfm                       Look for SFM Macintosh files
  --osx-double                Look for MacOS X AppleDouble Macintosh files
  --osx-hfs                   Look for MacOS X HFS Macintosh files

Report problems to debburn-devel@lists.alioth.debian.org.

Le chiffrement dans ce cas consiste à monter un système de fichiers sur lui-même. Le vérrouillage/dévérrouillage se fait par une de trois méthodes :

• Phrase de passe,
• tspi - une interface de chiffrement vers d'autres programmes,
• openssl.

Commencez par installer le paquet ecryptfs-utils dans la machine virtuelle :

SUSE12SP1:~ # zypper install ecryptfs-utils
Refreshing service 'SUSE_Linux_Enterprise_Server_12_SP1_x86_64'.
Loading repository data...
Reading installed packages...
Resolving package dependencies...

The following 14 NEW packages are going to be installed:
  ecryptfs-utils ecryptfs-utils-32bit gnome-keyring-32bit libgmp10-32bit libgnutls28-32bit libhogweed2-32bit libnettle4-32bit libp11-kit0-32bit
  libpkcs11-helper1 libpkcs11-helper1-32bit libtasn1-6-32bit libtspi1 libtspi1-32bit trousers

14 new packages to install.
Overall download size: 2.2 MiB. Already cached: 0 B. After the operation, additional 5.2 MiB will be used.
Continue? [y/n/? shows all options] (y): y

Démontez le système de fichiers btrfs sur /mnt :

SUSE12SP1:~ # umount /mnt
SUSE12SP1:~ # ls /mnt
lvm  sdb8  sdb9  testsnap

Montez maintenant /mnt/sdb8 sur lui-même :

SUSE12SP1:~ # mount -t ecryptfs /mnt/sdb8 /mnt/sdb8
Select key type to use for newly created files: 
 1) openssl
 2) passphrase
 3) pkcs11-helper
 4) tspi
Selection: 2
Passphrase: 
Select cipher: 
 1) aes: blocksize = 16; min keysize = 16; max keysize = 32
 2) blowfish: blocksize = 8; min keysize = 16; max keysize = 56
 3) des3_ede: blocksize = 8; min keysize = 24; max keysize = 24
 4) twofish: blocksize = 16; min keysize = 16; max keysize = 32
 5) cast6: blocksize = 16; min keysize = 16; max keysize = 32
 6) cast5: blocksize = 8; min keysize = 5; max keysize = 16
Selection [aes]: 1
Select key bytes: 
 1) 16
 2) 32
 3) 24
Selection [16]: 1
Enable plaintext passthrough (y/n) [n]: 
Enable filename encryption (y/n) [n]: y
Filename Encryption Key (FNEK) Signature [91aefde99b5a4977]: 
Attempting to mount with the following options:
  ecryptfs_unlink_sigs
  ecryptfs_fnek_sig=91aefde99b5a4977
  ecryptfs_key_bytes=16
  ecryptfs_cipher=aes
  ecryptfs_sig=91aefde99b5a4977
WARNING: Based on the contents of [/root/.ecryptfs/sig-cache.txt],
it looks like you have never mounted with this key 
before. This could mean that you have typed your 
passphrase wrong.

Would you like to proceed with the mount (yes/no)? : yes
Would you like to append sig [91aefde99b5a4977] to
[/root/.ecryptfs/sig-cache.txt] 
in order to avoid this warning in the future (yes/no)? : yes
Successfully appended new sig to user sig cache file
Mounted eCryptfs

Ce montage est visible dans la sortie de la commande df :

SUSE12SP1:~ # df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda2        18G  6.6G   11G  38% /
devtmpfs        815M  8.0K  815M   1% /dev
tmpfs           824M  144K  824M   1% /dev/shm
tmpfs           824M  9.8M  814M   2% /run
tmpfs           824M     0  824M   0% /sys/fs/cgroup
/dev/sda2        18G  6.6G   11G  38% /.snapshots
/dev/sda2        18G  6.6G   11G  38% /var/spool
/dev/sda2        18G  6.6G   11G  38% /var/opt
/dev/sda2        18G  6.6G   11G  38% /var/lib/named
/dev/sda2        18G  6.6G   11G  38% /var/lib/pgsql
/dev/sda2        18G  6.6G   11G  38% /var/tmp
/dev/sda2        18G  6.6G   11G  38% /var/lib/mariadb
/dev/sda2        18G  6.6G   11G  38% /var/lib/mysql
/dev/sda2        18G  6.6G   11G  38% /var/lib/mailman
/dev/sda2        18G  6.6G   11G  38% /usr/local
/dev/sda2        18G  6.6G   11G  38% /var/crash
/dev/sda2        18G  6.6G   11G  38% /var/lib/libvirt/images
/dev/sda2        18G  6.6G   11G  38% /tmp
/dev/sda2        18G  6.6G   11G  38% /opt
/dev/sda2        18G  6.6G   11G  38% /srv
/dev/sda2        18G  6.6G   11G  38% /boot/grub2/i386-pc
/dev/sda2        18G  6.6G   11G  38% /boot/grub2/x86_64-efi
/dev/sda2        18G  6.6G   11G  38% /home
/dev/sda2        18G  6.6G   11G  38% /var/log
/mnt/sdb8       477M  2.3M  445M   1% /mnt/sdb8

Plus de détails sont visibles avec la commande mount :

SUSE12SP1:~ # mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
...
/dev/sdb8 on /mnt/sdb8 type ext4 (rw,relatime,data=ordered)
/mnt/sdb8 on /mnt/sdb8 type ecryptfs (rw,relatime,ecryptfs_fnek_sig=91aefde99b5a4977,ecryptfs_sig=91aefde99b5a4977,ecryptfs_cipher=aes,ecryptfs_key_bytes=16,ecryptfs_unlink_sigs)

Créez maintenant le fichier encrypt contenant la chaîne de caractères fenestros dans /mnt/sdb8 :

SUSE12SP1:~ # touch /mnt/sdb8/encrypt
SUSE12SP1:~ # echo "fenestros" > /mnt/sdb8/encrypt
SUSE12SP1:~ # cat /mnt/sdb8/encrypt
fenestros

Démontez maintenant /mnt/sdb8 :

SUSE12SP1:~ # umount /mnt/sdb8
SUSE12SP1:~ # mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
...
/dev/sdb8 on /mnt/sdb8 type ext4 (rw,relatime,data=ordered)

Constatez maintenant le contenu de /mnt/sdb8 :

SUSE12SP1:~ # ls -l /mnt/sdb8
total 24
-rw-r--r-- 1 root root 12288 Oct 12 11:25 ECRYPTFS_FNEK_ENCRYPTED.FWaFfjrdapd7RkRCT3OFIdaE.-6mxquDYm8R4p7VFuV0SGgSJauuQJ2hEE--
drwx------ 2 root root 12288 Oct 11 13:42 lost+found

Constatez maintenant le contenu du fichier ECRYPTFS_FNEK_ENCRYPTED.FWaFfjrdapd7RkRCT3OFIdaE.-6mxquDYm8R4p7VFuV0SGgSJauuQJ2hEE– :

SUSE12SP1:~ # cat /mnt/sdb8/ECRYPTFS_FNEK_ENCRYPTED.FWaFfjrdapd7RkRCT3OFIdaE.-6mxquDYm8R4p7VFuV0SGgSJauuQJ2hEE--

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Y����S��YlOSUSE12SP1:~ # 

LUKS ( Linux Unified Key Setup ) permet de chiffrer l'intégralité d'un disque de telle sorte que celui-ci soit utilisable sur d'autres plates-formes et distributions de Linux (voire d'autres systèmes d'exploitation). Il supporte des mots de passe multiples, afin que plusieurs utilisateurs soient en mesure de déchiffrer le même volume sans partager leur mot de passe.

Remplissez la partition /dev/sdb9 avec des données aléatoires :

SUSE12SP1:~ # shred -v --iterations=1 /dev/sdb9
shred: /dev/sdb9: pass 1/1 (random)...
SUSE12SP1:~ # 

Initialisez la partition avec LUKS :

SUSE12SP1:~ # cryptsetup --verbose --verify-passphrase luksFormat /dev/sdb9

WARNING!
========
This will overwrite data on /dev/sdb9 irrevocably.

Are you sure? (Type uppercase yes): YES
Enter passphrase: fenestros123456789
Verify passphrase: fenestros123456789
Command successful.

Ouvrez la partition LUKS en lui donnant le nom sdb9 :

SUSE12SP1:~ # cryptsetup luksOpen /dev/sdb9 sdb9
Enter passphrase for /dev/sdb9:fenestros123456789

Vérifiez que le système voit la partition :

SUSE12SP1:~ # ls -l /dev/mapper | grep sdb9
lrwxrwxrwx 1 root root       7 Oct 12 11:38 sdb9 -> ../dm-2

Créez maintenant un système de fichiers sur /dev/mapper/sdb9 :

SUSE12SP1:~ # mkfs.ext4 /dev/mapper/sdb9
mke2fs 1.42.11 (09-Jul-2014)
Creating filesystem with 202752 1k blocks and 50800 inodes
Filesystem UUID: a37da1b7-7381-49e4-9c99-819671b12ebc
Superblock backups stored on blocks: 
	8193, 24577, 40961, 57345, 73729

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done 

Montez la partition LUKS :

SUSE12SP1:~ # mount /dev/mapper/sdb9 /mnt/sdb9

Vérifiez la présence du montage :

SUSE12SP1:~ # df -h | grep sdb9
/dev/mapper/sdb9  188M  1.6M  173M   1% /mnt/sdb9

Editez le fichier /etc/crypttab/ :

SUSE12SP1:~ # vi /etc/crypttab
SUSE12SP1:~ # cat /etc/crypttab
sdb9	/dev/sdb9	none

Modifiez le fichier /etc/fstab :

SUSE12SP1:~ # vi /etc/fstab
SUSE12SP1:~ # cat /etc/fstab
UUID=9e0e4497-5e47-419a-8ff4-9e2dd7d6a11b swap swap defaults 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 / btrfs defaults 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /boot/grub2/i386-pc btrfs subvol=@/boot/grub2/i386-pc 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /boot/grub2/x86_64-efi btrfs subvol=@/boot/grub2/x86_64-efi 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /home btrfs subvol=@/home 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /opt btrfs subvol=@/opt 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /srv btrfs subvol=@/srv 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /tmp btrfs subvol=@/tmp 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /usr/local btrfs subvol=@/usr/local 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/crash btrfs subvol=@/var/crash 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/lib/libvirt/images btrfs subvol=@/var/lib/libvirt/images 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/lib/mailman btrfs subvol=@/var/lib/mailman 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/lib/mariadb btrfs subvol=@/var/lib/mariadb 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/lib/mysql btrfs subvol=@/var/lib/mysql 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/lib/named btrfs subvol=@/var/lib/named 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/lib/pgsql btrfs subvol=@/var/lib/pgsql 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/log btrfs subvol=@/var/log 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/opt btrfs subvol=@/var/opt 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/spool btrfs subvol=@/var/spool 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /var/tmp btrfs subvol=@/var/tmp 0 0
UUID=65337196-2d6b-4c8b-b917-30c3867bf265 /.snapshots btrfs subvol=@/.snapshots 0 0
/dev/mapper/sdb9	/mnt/sdb9	ext4	defaults	1 2

Redémarrez votre machine virtuelle :

SUSE12SP1:~ # shutdown -r now

Pour ajouter une deuxième passphrase, utilisez la commande cryptsetup avec la sous-commande luksAddKey :

SUSE12SP1:~ # cryptsetup luksAddKey /dev/sdb9
Enter any existing passphrase: fenestros123456789
Enter new passphrase for key slot: sles123456789
Verify passphrase: 
SUSE12SP1:~ #  

Pour supprimer une passphrase, utilisez la commande cryptsetup avec la sous-commande luksRemoveKey :

SUSE12SP1:~ # cryptsetup luksRemoveKey /dev/sdb9
Enter passphrase to be deleted: 
SUSE12SP1:~ # sles123456789

Le tableau suivant résume la taille du swap recommandée en fonction de la mémoire de la machine :

Une partition de swap peut être créée sur :

• une partition du disque dur
• un RAID logiciel
• un Volume Logique

Pour préparer un espace de swap, il convient d'utiliser la commande mkswap. Pour activer une partition de swap, il convient d'utiliser la commande swapon. Pour consulter la liste des partitions swap, il convient d'utiliser la commande swapon avec l'option -s.

SUSE12SP1:~ # swapon -s
Filename				Type		Size	Used	Priority
/dev/sda1                              	partition	2103292	0	-1

Les options de la commande swapon sont :

SUSE12SP1:~ # swapon --help

Usage:
 swapon [options] [<spec>]

Options:
 -a, --all                enable all swaps from /etc/fstab
 -d, --discard[=<policy>] enable swap discards, if supported by device
 -e, --ifexists           silently skip devices that do not exist
 -f, --fixpgsz            reinitialize the swap space if necessary
 -p, --priority <prio>    specify the priority of the swap device
 -s, --summary            display summary about used swap devices (DEPRECATED)
     --show[=<columns>]   display summary in definable table
     --noheadings         don't print headings, use with --show
     --raw                use the raw output format, use with --show
     --bytes              display swap size in bytes in --show output
 -v, --verbose            verbose mode

 -h, --help     display this help and exit
 -V, --version  output version information and exit

The <spec> parameter:
 -L <label>             synonym for LABEL=<label>
 -U <uuid>              synonym for UUID=<uuid>
 LABEL=<label>          specifies device by swap area label
 UUID=<uuid>            specifies device by swap area UUID
 PARTLABEL=<label>      specifies device by partition label
 PARTUUID=<uuid>        specifies device by partition UUID
 <device>               name of device to be used
 <file>                 name of file to be used

Available discard policy types (for --discard):
 once	  : only single-time area discards are issued. (swapon)
 pages	  : discard freed pages before they are reused.
 * if no policy is selected both discard types are enabled. (default)

Available columns (for --show):
 NAME  device file or partition path
 TYPE  type of the device
 SIZE  size of the swap area
 USED  bytes in use
 PRIO  swap priority

For more details see swapon(8).

Dans le cas de notre exemple, la partition de swap se trouve sur /dev/sda1. Pour la désactiver, il convient de saisir la commande suivante :

SUSE12SP1:~ # swapoff /dev/sda1
SUSE12SP1:~ # swapon -s
SUSE12SP1:~ # 

SUSE12SP1:~ # swapoff --help

Usage:
 swapoff [options] [<spec>]

Options:
 -a, --all              disable all swaps from /proc/swaps
 -v, --verbose          verbose mode

 -h, --help     display this help and exit
 -V, --version  output version information and exit

The <spec> parameter:
 -L <label>             LABEL of device to be used
 -U <uuid>              UUID of device to be used
 LABEL=<label>          LABEL of device to be used
 UUID=<uuid>            UUID of device to be used
 <device>               name of device to be used
 <file>                 name of file to be used

For more details see swapoff(8).

Remettez en place votre swap :

SUSE12SP1:~ # swapon -p1 /dev/sda1
SUSE12SP1:~ # swapon -s
Filename				Type		Size	Used	Priority
/dev/sda1                              	partition	2103292	0	1

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