Version : 2024.01

Dernière mise-à-jour :

LDF607 - Gestion du Noyau et des Quotas

Contenu du Module

LDF607 - Gestion du Noyau et des Quotas

Contenu du Module

Rôle du noyau

LAB #1 - Compilation et installation du noyau

1.1 - Déplacer /home

1.2 - Télécharger le Code Source du Noyau

1.3 - Configurer le Noyau

1.4 - Compiler le Noyau

1.5 - Installer le Nouveau Noyau

1.6 - Désinstaller un Noyau

LAB #2 - Mise à Jour du Noyau avec le Gestionnaire des Paquets

LAB #3 - Gestion des Quotas

3.1 - La Commande quotacheck

3.2 - La Commande edquota

3.3 - La Commande quotaon

3.4 - La Commande repquota

3.5 - La Commande quota

3.6 - La Commande warnquota

Rôle du noyau

Le noyau ou kernel est la partie du système d'exploitation qui gère les entrées/sorties avec des périphériques. Dans certains cas il est préférable de recompiler le noyau de Linux. La motivation de cette recompilation peut être :

la diminution de la taille du noyau,

la prise en charge de nouveau matériel,

l'ajout de fonctionnalités,

l'optimisation du code,

la correction de bogues,

le besoin d'une fonctionnalité expérimentale.

Commencez par identifier le noyau utilisé par votre machine :

root@debian11:~# uname -r
5.10.0-13-amd64

Dans le cas d'une utilisation courante de Linux, il est cependant préférable de faire appel aux modules. Les modules se trouvent dans le répertoire /lib/modules/<version-du-noyau> :

root@debian11:~# ls /lib/modules/`uname -r`/
kernel modules.alias.bin modules.builtin.alias.bin modules.builtin.modinfo modules.dep.bin modules.order modules.symbols
modules.alias modules.builtin modules.builtin.bin modules.dep modules.devname modules.softdep modules.symbols.bin

Les commandes pour manipuler les modules sont :

insmod

rmmod

lsmod

modprobe

Par exemple :

root@debian11:~# lsmod
Module Size Used by
rfkill 28672 1
raid456 180224 1
async_raid6_recov 24576 1 raid456
async_memcpy 20480 2 raid456,async_raid6_recov
async_pq 20480 2 raid456,async_raid6_recov
async_xor 20480 3 async_pq,raid456,async_raid6_recov
async_tx 20480 5 async_pq,async_memcpy,async_xor,raid456,async_raid6_recov
md_mod 180224 1 raid456
sg 36864 0
virtio_balloon 24576 0
joydev 28672 0
qemu_fw_cfg 20480 0
pcspkr 16384 0
serio_raw 20480 0
evdev 28672 2
ecryptfs 122880 0
parport_pc 40960 0
ppdev 24576 0
lp 20480 0
parport 69632 3 parport_pc,lp,ppdev
fuse 167936 1
configfs 57344 1
ip_tables 32768 0
x_tables 53248 1 ip_tables
autofs4 53248 2
ext4 921600 1
crc16 16384 1 ext4
mbcache 16384 1 ext4
jbd2 151552 1 ext4
hid_generic 16384 0
btrfs 1568768 0
usbhid 65536 0
hid 147456 2 usbhid,hid_generic
blake2b_generic 20480 0
xor 24576 2 async_xor,btrfs
raid6_pq 122880 4 async_pq,btrfs,raid456,async_raid6_recov
libcrc32c 16384 2 btrfs,raid456
crc32c_generic 16384 3
usb_storage 81920 0
dm_mod 163840 4
sd_mod 61440 10
t10_pi 16384 1 sd_mod
crc_t10dif 20480 1 t10_pi
crct10dif_generic 16384 1
crct10dif_common 16384 2 crct10dif_generic,crc_t10dif
sr_mod 28672 0
cdrom 73728 1 sr_mod
virtio_net 61440 0
net_failover 24576 1 virtio_net
failover 16384 1 net_failover
virtio_scsi 24576 8
bochs_drm 16384 0
ata_generic 16384 0
drm_vram_helper 20480 1 bochs_drm
uhci_hcd 53248 0
drm_ttm_helper 16384 1 drm_vram_helper
ttm 114688 2 drm_vram_helper,drm_ttm_helper
ehci_hcd 98304 0
drm_kms_helper 278528 4 drm_vram_helper,bochs_drm
cec 61440 1 drm_kms_helper
psmouse 184320 0
drm 618496 6 drm_kms_helper,drm_vram_helper,bochs_drm,drm_ttm_helper,ttm
usbcore 323584 4 usbhid,usb_storage,ehci_hcd,uhci_hcd
ata_piix 36864 0
virtio_pci 28672 0
libata 290816 2 ata_piix,ata_generic
virtio_ring 36864 4 virtio_balloon,virtio_scsi,virtio_pci,virtio_net
virtio 16384 4 virtio_balloon,virtio_scsi,virtio_pci,virtio_net
i2c_piix4 28672 0
scsi_mod 262144 6 virtio_scsi,sd_mod,usb_storage,libata,sg,sr_mod
usb_common 16384 3 usbcore,ehci_hcd,uhci_hcd
floppy 90112 0
button 24576 0

Pour ajouter un module, on peut utiliser la commande insmod ou modprobe. Cette dernière ajoute non seulement le module passé en argument mais également ses dépendances :

root@debian11:~# modprobe bonding
root@debian11:~# lsmod | head
Module Size Used by
bonding 192512 0
rfkill 28672 1
raid456 180224 1
async_raid6_recov 24576 1 raid456
async_memcpy 20480 2 raid456,async_raid6_recov
async_pq 20480 2 raid456,async_raid6_recov
async_xor 20480 3 async_pq,raid456,async_raid6_recov
async_tx 20480 5 async_pq,async_memcpy,async_xor,raid456,async_raid6_recov
md_mod 180224 1 raid456

Pour supprimer un module, on peut utiliser la commande rmmod ou modprobe -r. Cette dernière essaie de supprimer les dépendances non-utilisées :

root@debian11:~# modprobe -r bonding
root@debian11:~# lsmod | head
Module Size Used by
rfkill 28672 1
raid456 180224 1
async_raid6_recov 24576 1 raid456
async_memcpy 20480 2 raid456,async_raid6_recov
async_pq 20480 2 raid456,async_raid6_recov
async_xor 20480 3 async_pq,raid456,async_raid6_recov
async_tx 20480 5 async_pq,async_memcpy,async_xor,raid456,async_raid6_recov
md_mod 180224 1 raid456
sg 36864 0

Les dépendances des modules sont résolues par la commande modprobe grâce aux fichier /lib/modules/<version-du-noyau>/modules.dep. Ce dernier peut être créé manuellement grâce à la commande depmod :

root@debian11:~# more /lib/modules/`uname -r`/modules.dep
kernel/arch/x86/events/amd/power.ko:
kernel/arch/x86/events/intel/intel-uncore.ko:
kernel/arch/x86/events/intel/intel-cstate.ko:
kernel/arch/x86/events/rapl.ko:
kernel/arch/x86/kernel/cpu/mce/mce-inject.ko:
kernel/arch/x86/kernel/msr.ko:
kernel/arch/x86/kernel/cpuid.ko:
kernel/arch/x86/crypto/glue_helper.ko:
kernel/arch/x86/crypto/twofish-x86_64.ko: kernel/crypto/twofish_common.ko
kernel/arch/x86/crypto/twofish-x86_64-3way.ko: kernel/arch/x86/crypto/twofish-x86_64.ko kernel/crypto/twofish_common.ko kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/twofish-avx-x86_64.ko: kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko kernel/arch/x86/crypto/twofish-x86_64-3way.ko kernel/arch/x86/crypto/twofish-x86_64.ko kernel/crypto/twofish_co
mmon.ko kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/serpent-sse2-x86_64.ko: kernel/crypto/serpent_generic.ko kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/serpent-avx-x86_64.ko: kernel/crypto/serpent_generic.ko kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/serpent-avx2.ko: kernel/arch/x86/crypto/serpent-avx-x86_64.ko kernel/crypto/serpent_generic.ko kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/des3_ede-x86_64.ko: kernel/lib/crypto/libdes.ko
kernel/arch/x86/crypto/camellia-x86_64.ko: kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/camellia-aesni-avx-x86_64.ko: kernel/arch/x86/crypto/camellia-x86_64.ko kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/camellia-aesni-avx2.ko: kernel/arch/x86/crypto/camellia-aesni-avx-x86_64.ko kernel/arch/x86/crypto/camellia-x86_64.ko kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko kernel/arch/x86/
crypto/glue_helper.ko
kernel/arch/x86/crypto/blowfish-x86_64.ko: kernel/crypto/blowfish_common.ko
kernel/arch/x86/crypto/cast5-avx-x86_64.ko: kernel/crypto/cast5_generic.ko kernel/crypto/cast_common.ko kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko
kernel/arch/x86/crypto/cast6-avx-x86_64.ko: kernel/crypto/cast6_generic.ko kernel/crypto/cast_common.ko kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/aegis128-aesni.ko: kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko
kernel/arch/x86/crypto/chacha-x86_64.ko: kernel/lib/crypto/libchacha.ko
kernel/arch/x86/crypto/aesni-intel.ko: kernel/lib/crypto/libaes.ko kernel/crypto/crypto_simd.ko kernel/crypto/cryptd.ko kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/sha1-ssse3.ko:
kernel/arch/x86/crypto/sha256-ssse3.ko:
kernel/arch/x86/crypto/sha512-ssse3.ko: kernel/crypto/sha512_generic.ko
kernel/arch/x86/crypto/blake2s-x86_64.ko: kernel/lib/crypto/libblake2s-generic.ko
kernel/arch/x86/crypto/ghash-clmulni-intel.ko: kernel/crypto/cryptd.ko
kernel/arch/x86/crypto/crc32c-intel.ko:
kernel/arch/x86/crypto/crc32-pclmul.ko:
kernel/arch/x86/crypto/crct10dif-pclmul.ko: kernel/crypto/crct10dif_common.ko
kernel/arch/x86/crypto/poly1305-x86_64.ko:
kernel/arch/x86/crypto/curve25519-x86_64.ko: kernel/lib/crypto/libcurve25519-generic.ko
kernel/arch/x86/kvm/kvm.ko: kernel/virt/lib/irqbypass.ko
kernel/arch/x86/kvm/kvm-intel.ko: kernel/arch/x86/kvm/kvm.ko kernel/virt/lib/irqbypass.ko
kernel/arch/x86/kvm/kvm-amd.ko: kernel/drivers/crypto/ccp/ccp.ko kernel/drivers/char/hw_random/rng-core.ko kernel/arch/x86/kvm/kvm.ko kernel/virt/lib/irqbypass.ko
kernel/mm/hwpoison-inject.ko:
kernel/mm/zsmalloc.ko:
kernel/mm/z3fold.ko:
kernel/fs/nfs_common/nfs_acl.ko: kernel/net/sunrpc/sunrpc.ko
kernel/fs/nfs_common/grace.ko:
kernel/fs/nfs_common/nfs_ssc.ko:
kernel/fs/quota/quota_v1.ko:
kernel/fs/quota/quota_v2.ko: kernel/fs/quota/quota_tree.ko
kernel/fs/quota/quota_tree.ko:
kernel/fs/nls/nls_cp437.ko:
kernel/fs/nls/nls_cp737.ko:
kernel/fs/nls/nls_cp775.ko:
kernel/fs/nls/nls_cp850.ko:
kernel/fs/nls/nls_cp852.ko:
kernel/fs/nls/nls_cp855.ko:
kernel/fs/nls/nls_cp857.ko:
kernel/fs/nls/nls_cp860.ko:
kernel/fs/nls/nls_cp861.ko:
kernel/fs/nls/nls_cp862.ko:
--More--(0%)
[q]

Il est possible d'obtenir des informations sur un module grâce à la commande modinfo :

root@debian11:~# modinfo bonding
filename: /lib/modules/5.10.0-13-amd64/kernel/drivers/net/bonding/bonding.ko
author: Thomas Davis, tadavis@lbl.gov and many others
description: Ethernet Channel Bonding Driver
license: GPL
alias: rtnl-link-bond
depends:
retpoline: Y
intree: Y
name: bonding
vermagic: 5.10.0-13-amd64 SMP mod_unload modversions
sig_id: PKCS#7
signer: Debian Secure Boot CA
sig_key: 4B:6E:F5:AB:CA:66:98:25:17:8E:05:2C:84:66:7C:CB:C0:53:1F:8C
sig_hashalgo: sha256
signature: 52:9F:34:1A:E8:04:22:2E:4C:92:17:82:D2:22:83:59:38:E2:EB:D6:
EC:81:C3:CD:F8:C1:B9:5F:FC:C2:6D:27:BC:7B:91:13:87:5B:2E:92:
77:36:A1:3D:F8:41:5C:9B:1D:62:E1:90:F7:48:F4:4E:7E:85:F5:54:
CD:51:99:A6:C4:E0:FB:2C:4F:D6:5F:11:15:93:7E:30:62:A9:FA:46:
29:90:B2:58:A4:B4:34:8B:EA:EF:14:AD:D6:5D:6C:4D:03:C9:AC:0F:
F1:28:A0:65:3C:AA:C8:CA:83:59:25:F3:09:20:F2:74:7F:5A:7D:BB:
84:17:57:F5:E6:16:E5:CB:A9:A3:0C:F0:A9:04:4A:B2:63:98:80:30:
73:EE:39:3A:86:3E:67:3C:2F:5C:38:1E:35:F9:79:6C:F6:60:7B:B5:
9D:3C:EA:0D:0F:23:E1:EC:EA:42:4C:EF:EC:AB:3E:07:D3:35:D7:E4:
4A:E4:D1:7A:50:F8:C1:50:5E:93:0C:A2:7D:D1:77:E2:3A:97:74:BA:
D7:38:7E:C0:4C:36:66:00:78:03:E0:E3:20:46:70:13:7D:15:10:3A:
85:B7:CB:10:3B:9A:DF:1A:4E:64:3D:BF:EC:21:7B:B1:4C:37:CE:30:
0D:90:FE:73:87:20:40:83:60:02:0F:4F:4D:85:78:E7
parm: max_bonds:Max number of bonded devices (int)
parm: tx_queues:Max number of transmit queues (default = 16) (int)
parm: num_grat_arp:Number of peer notifications to send on failover event (alias of num_unsol_na) (int)
parm: num_unsol_na:Number of peer notifications to send on failover event (alias of num_grat_arp) (int)
parm: miimon:Link check interval in milliseconds (int)
parm: updelay:Delay before considering link up, in milliseconds (int)
parm: downdelay:Delay before considering link down, in milliseconds (int)
parm: use_carrier:Use netif_carrier_ok (vs MII ioctls) in miimon; 0 for off, 1 for on (default) (int)
parm: mode:Mode of operation; 0 for balance-rr, 1 for active-backup, 2 for balance-xor, 3 for broadcast, 4 for 802.3ad, 5 for balance-tlb, 6 for balance-alb (charp)
parm: primary:Primary network device to use (charp)
parm: primary_reselect:Reselect primary slave once it comes up; 0 for always (default), 1 for only if speed of primary is better, 2 for only on active slave failure (charp)
parm: lacp_rate:LACPDU tx rate to request from 802.3ad partner; 0 for slow, 1 for fast (charp)
parm: ad_select:802.3ad aggregation selection logic; 0 for stable (default), 1 for bandwidth, 2 for count (charp)
parm: min_links:Minimum number of available links before turning on carrier (int)
parm: xmit_hash_policy:balance-alb, balance-tlb, balance-xor, 802.3ad hashing method; 0 for layer 2 (default), 1 for layer 3+4, 2 for layer 2+3, 3 for encap layer 2+3, 4 for encap layer 3+4 (charp)
parm: arp_interval:arp interval in milliseconds (int)
parm: arp_ip_target:arp targets in n.n.n.n form (array of charp)
parm: arp_validate:validate src/dst of ARP probes; 0 for none (default), 1 for active, 2 for backup, 3 for all (charp)
parm: arp_all_targets:fail on any/all arp targets timeout; 0 for any (default), 1 for all (charp)
parm: fail_over_mac:For active-backup, do not set all slaves to the same MAC; 0 for none (default), 1 for active, 2 for follow (charp)
parm: all_slaves_active:Keep all frames received on an interface by setting active flag for all slaves; 0 for never (default), 1 for always. (int)
parm: resend_igmp:Number of IGMP membership reports to send on link failure (int)
parm: packets_per_slave:Packets to send per slave in balance-rr mode; 0 for a random slave, 1 packet per slave (default), >1 packets per slave. (int)
parm: lp_interval:The number of seconds between instances where the bonding driver sends learning packets to each slaves peer switch. The default is 1. (uint)

Dernièrement, les fichiers dans le repertoire /etc/modprobe.d sont utilisés pour spécifier les options éventuelles à passer aux modules lors de leur chargement ainsi que les alias utilisés pour leur faire référence :

root@debian11:~# ls /etc/modprobe.d
mdadm.conf
root@debian11:~# cat /etc/modprobe.d/mdadm.conf
# mdadm module configuration file
# set start_ro=1 to make newly assembled arrays read-only initially,
# to prevent metadata writes. This is needed in order to allow
# resume-from-disk to work - new boot should not perform writes
# because it will be done behind the back of the system being
# resumed. See http://bugs.debian.org/415441 for details.
options md_mod start_ro=1

LAB #1 - Compilation et installation du noyau

Commencez par installer les paquets necessaires :

root@debian11:~# apt-get update
Hit:1 http://deb.debian.org/debian bullseye InRelease
Get:2 http://deb.debian.org/debian bullseye-updates InRelease [39.4 kB]
Get:3 http://security.debian.org/debian-security bullseye-security InRelease [44.1 kB]
Fetched 83.5 kB in 1s (158 kB/s)
Reading package lists... Done
root@debian11:~# apt-get -y install build-essential linux-source bc kmod cpio flex libncurses5-dev libelf-dev libssl-dev dwarves debconf-utils dpkg-dev debhelper ncurses-dev libelf-dev flex bison rsync libssl-dev

1.1 - Déplacer /home

Créez une seule partition sur /dev/sdb :

root@debian11:~# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.36.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table.
Created a new DOS disklabel with disk identifier 0xa10c368d.
Command (m for help): n
Partition type
p primary (0 primary, 0 extended, 4 free)
e extended (container for logical partitions)
Select (default p):
Using default response p.
Partition number (1-4, default 1):
First sector (2048-134217727, default 2048):
Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-134217727, default 134217727):
Created a new partition 1 of type 'Linux' and of size 64 GiB.
Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

Créez maintenant un système de fichiers ext4 sur /dev/sdb1 :

root@debian11:~# mkfs.ext4 /dev/sdb1
mke2fs 1.46.2 (28-Feb-2021)
Discarding device blocks: done
Creating filesystem with 16776960 4k blocks and 4194304 inodes
Filesystem UUID: 24f1821e-1d5b-4256-8ee3-c9ee6b382ddc
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424
Allocating group tables: done
Writing inode tables: done
Creating journal (65536 blocks): done
Writing superblocks and filesystem accounting information: done

Editez le fichier /etc/ssh/sshd_config et modifiez la directive PermitRootLogin :

root@debian11:~# vi /etc/ssh/sshd_config
root@debian11:~# cat /etc/ssh/sshd_config
# $OpenBSD: sshd_config,v 1.103 2018/04/09 20:41:22 tj Exp $
# This is the sshd server system-wide configuration file. See
# sshd_config(5) for more information.
# This sshd was compiled with PATH=/usr/bin:/bin:/usr/sbin:/sbin
# The strategy used for options in the default sshd_config shipped with
# OpenSSH is to specify options with their default value where
# possible, but leave them commented. Uncommented options override the
# default value.
Include /etc/ssh/sshd_config.d/*.conf
#Port 22
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress ::
#HostKey /etc/ssh/ssh_host_rsa_key
#HostKey /etc/ssh/ssh_host_ecdsa_key
#HostKey /etc/ssh/ssh_host_ed25519_key
# Ciphers and keying
#RekeyLimit default none
# Logging
#SyslogFacility AUTH
#LogLevel INFO
# Authentication:
#LoginGraceTime 2m
PermitRootLogin yes
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10
...

Re-démarrez le serveur ssh :

root@debian11:~# systemctl restart sshd
root@debian11:~# systemctl status sshd
● ssh.service - OpenBSD Secure Shell server
Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
Active: active (running) since Sun 2022-05-01 15:35:50 CEST; 6s ago
Docs: man:sshd(8)
man:sshd_config(5)
Process: 2793 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=0/SUCCESS)
Main PID: 2794 (sshd)
Tasks: 1 (limit: 4656)
Memory: 1.1M
CPU: 25ms
CGroup: /system.slice/ssh.service
└─2794 sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups
May 01 15:35:50 debian11 systemd[1]: Starting OpenBSD Secure Shell server...
May 01 15:35:50 debian11 sshd[2794]: Server listening on 0.0.0.0 port 22.
May 01 15:35:50 debian11 sshd[2794]: Server listening on :: port 22.
May 01 15:35:50 debian11 systemd[1]: Started OpenBSD Secure Shell server.

A Faire - Déconnectez-vous en ssh. Connectez-vous directement en tant que root en ssh.

Montez /dev/sdb1 sur /mnt :

root@debian11:~# mount /dev/sdb1 /mnt

Copiez le contenu de /home vers /mnt :

root@debian11:~# cp -a /home/* /mnt

Démontez /dev/sdb1 :

root@debian11:~# umount /mnt

Identifiez l'UUID de /dev/sdb1 :

root@debian11:~# ls -l /dev/disk/by-uuid/ | grep sdb1
lrwxrwxrwx 1 root root 10 May 1 15:31 24f1821e-1d5b-4256-8ee3-c9ee6b382ddc -> ../../sdb1

Editez le fichier /etc/fstab en ajoutant la ligne pour le montage de /home :

root@debian11:~# vi /etc/fstab
root@debian11:~# cat /etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# systemd generates mount units based on this file, see systemd.mount(5).
# Please run 'systemctl daemon-reload' after making changes here.
#
# <file system> <mount point> <type> <options> <dump> <pass>
# / was on /dev/sda1 during installation
UUID=9887a74f-a680-4bde-8f04-db5ae9ea186e / ext4 errors=remount-ro 0 1
UUID=24f1821e-1d5b-4256-8ee3-c9ee6b382ddc /home ext4 defaults 0 0
# swap was on /dev/sda5 during installation
UUID=1f9439f5-4b19-49b1-b292-60c2c674cee9 none swap sw 0 0
/dev/sr0 /media/cdrom0 udf,iso9660 user,noauto 0 0

Créez le point de montage /home :

root@debian11:~# rm -rf /home
root@debian11:~# mkdir /home

Montez /dev/sdb1 :

root@debian11:~# mount -a
root@debian11:~# mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=1986968k,nr_inodes=496742,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,size=402560k,mode=755)
/dev/sda1 on / type ext4 (rw,relatime,errors=remount-ro)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
none on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=29,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=11732)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
tmpfs on /run/user/0 type tmpfs (rw,nosuid,nodev,relatime,size=402556k,nr_inodes=100639,mode=700)
/dev/sdb1 on /home type ext4 (rw,relatime)

Notez la taille de /home :

root@debian11:~# df -h
Filesystem Size Used Avail Use% Mounted on
udev 1.9G 0 1.9G 0% /dev
tmpfs 394M 892K 393M 1% /run
/dev/sda1 31G 4.1G 25G 14% /
tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 394M 36K 394M 1% /run/user/0
/dev/sdb1 63G 1.4M 60G 1% /home

A Faire - Fermez la session de root et connectez-vous en tant que trainee en ssh.

1.2 - Télécharger le Code Source du Noyau

Le code source est disponible sur le site www.kernel.org :

trainee@debian11:~$ wget https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/linux-5.11.1.tar.gz

Désarchivez le tar.xz que vous avez téléchargé :

trainee@debian8:~$ tar xf linux-5.11.1.tar.gz

Notez que l'occupation disque du code source du noyau linux-5.11.1 est de 1.2 Go :

trainee@debian11:~$ du -hs ./linux-5.11.1
1.2G ./linux-5.11.1

1.3 - Configurer le Noyau

Le fichier Makefile contient le nom du noyau et spécifie les informations suivantes :

VERSION,

PATCHLEVEL,

SUBLEVEL,

EXTRAVERSION.

Les trois premières informations sont gérées par kernel.org et Linus Torvalds en personne tandis que l'EXTRAVERSION est gérée par Debian :

trainee@debian11:~$ cat ./linux-5.11.1/Makefile | head
# SPDX-License-Identifier: GPL-2.0
VERSION = 5
PATCHLEVEL = 11
SUBLEVEL = 1
EXTRAVERSION =
NAME = 💕 Valentine's Day Edition 💕
# *DOCUMENTATION*
# To see a list of typical targets execute "make help"
# More info can be located in ./README

Important - La version 2.6 du noyau a vu le jour en 2003. Les SUBLEVEL se suivaient régulièrement. Avec la version 2.6 du noyau, la valeur paire du PATCHLEVEL indiquait que le noyau était stable. Quand vous recompilez le noyau à partir des sources, vous devez modifier la valeur de l'EXTRAVERSION. Le passage à la version 3.0 fut décidé par Linus Torvalds à l'occasion des 20 ans du noyau Linux.

Utilisez maintenant la commande make defconfig pour créer le fichier de configuration .config :

trainee@debian11:~$ su -
Password: fenestros
root@debian11:~# cd /home/trainee/linux-5.11.1/
root@debian11:/home/trainee/linux-5.11.1# make defconfig
HOSTCC scripts/basic/fixdep
HOSTCC scripts/kconfig/conf.o
HOSTCC scripts/kconfig/confdata.o
HOSTCC scripts/kconfig/expr.o
LEX scripts/kconfig/lexer.lex.c
YACC scripts/kconfig/parser.tab.[ch]
HOSTCC scripts/kconfig/lexer.lex.o
HOSTCC scripts/kconfig/parser.tab.o
HOSTCC scripts/kconfig/preprocess.o
HOSTCC scripts/kconfig/symbol.o
HOSTCC scripts/kconfig/util.o
HOSTLD scripts/kconfig/conf
*** Default configuration is based on 'x86_64_defconfig'
#
# configuration written to .config
#

Ce fichier est configuré par une des trois commandes suivantes :

make config

make menuconfig

make xconfig

Dans ce fichier, vous pouvez constater la présence de lignes correspondantes à des fonctionalités suivies par une lettre ou une valeur. Dans le cas d'une lettre, la signification est la suivante :

y

la fonctionnalité est incluse dans le noyau monolithique ou dans le cas d'une dépendance d'un module, dans le module concerné,

m

la fonctionnalité est incluse en tant que module,

n

la fonctionnalité n'est pas incluse. Cette option est rarement visible car dans bien les cas, la fonctionnalité est simplement commentée dans le fichier lui-même.

root@debian11:/home/trainee/linux-5.11.1# more .config
#
# Automatically generated file; DO NOT EDIT.
# Linux/x86 5.11.1 Kernel Configuration
#
CONFIG_CC_VERSION_TEXT="gcc (Debian 10.2.1-6) 10.2.1 20210110"
CONFIG_CC_IS_GCC=y
CONFIG_GCC_VERSION=100201
CONFIG_LD_VERSION=235020000
CONFIG_CLANG_VERSION=0
CONFIG_LLD_VERSION=0
CONFIG_CC_CAN_LINK=y
CONFIG_CC_CAN_LINK_STATIC=y
CONFIG_CC_HAS_ASM_GOTO=y
CONFIG_CC_HAS_ASM_INLINE=y
CONFIG_IRQ_WORK=y
CONFIG_BUILDTIME_TABLE_SORT=y
CONFIG_THREAD_INFO_IN_TASK=y
#
# General setup
#
CONFIG_INIT_ENV_ARG_LIMIT=32
# CONFIG_COMPILE_TEST is not set
CONFIG_LOCALVERSION=""
# CONFIG_LOCALVERSION_AUTO is not set
CONFIG_BUILD_SALT=""
CONFIG_HAVE_KERNEL_GZIP=y
CONFIG_HAVE_KERNEL_BZIP2=y
CONFIG_HAVE_KERNEL_LZMA=y
CONFIG_HAVE_KERNEL_XZ=y
CONFIG_HAVE_KERNEL_LZO=y
CONFIG_HAVE_KERNEL_LZ4=y
CONFIG_HAVE_KERNEL_ZSTD=y
CONFIG_KERNEL_GZIP=y
# CONFIG_KERNEL_BZIP2 is not set
# CONFIG_KERNEL_LZMA is not set
# CONFIG_KERNEL_XZ is not set
# CONFIG_KERNEL_LZO is not set
# CONFIG_KERNEL_LZ4 is not set
# CONFIG_KERNEL_ZSTD is not set
CONFIG_DEFAULT_INIT=""
CONFIG_DEFAULT_HOSTNAME="(none)"
CONFIG_SWAP=y
CONFIG_SYSVIPC=y
CONFIG_SYSVIPC_SYSCTL=y
CONFIG_POSIX_MQUEUE=y
CONFIG_POSIX_MQUEUE_SYSCTL=y
# CONFIG_WATCH_QUEUE is not set
CONFIG_CROSS_MEMORY_ATTACH=y
CONFIG_USELIB=y
CONFIG_AUDIT=y
CONFIG_HAVE_ARCH_AUDITSYSCALL=y
CONFIG_AUDITSYSCALL=y
#
# IRQ subsystem
#
CONFIG_GENERIC_IRQ_PROBE=y
--More--(1%)
[q]

1.4 - Compiler le Noyau

La compilation du noyau peut prendre beaucoup de temps. La commande utilisée est la suivante :

root@debian11:/home/trainee/linux-5.11.1# make deb-pkg clean
...
dpkg-buildpackage: info: full upload (original source is included)
CLEAN arch/x86/entry/vdso
CLEAN arch/x86/kernel/cpu
CLEAN arch/x86/kernel
CLEAN arch/x86/realmode/rm
CLEAN arch/x86/lib
CLEAN certs
CLEAN drivers/firmware/efi/libstub
CLEAN drivers/scsi
CLEAN drivers/tty/vt
CLEAN drivers/video/logo
CLEAN lib
CLEAN net/wireless
CLEAN security/selinux
CLEAN usr/include
CLEAN usr
CLEAN arch/x86/boot/compressed
CLEAN arch/x86/boot
CLEAN arch/x86/tools
CLEAN vmlinux.symvers modules.builtin modules.builtin.modinfo

A l'issu du processus, les paquets du nouveau noyau se trouvent dans le répertoire /home/trainee :

root@debian11:/home/trainee/linux-5.11.1# cd ..
root@debian11:/home/trainee# ls
Desktop linux-5.11.1 linux-5.11.1_5.11.1-1.diff.gz linux-5.11.1.tar.gz linux-libc-dev_5.11.1-1_amd64.deb Public
Documents linux-5.11.1_5.11.1-1_amd64.buildinfo linux-5.11.1_5.11.1-1.dsc linux-headers-5.11.1_5.11.1-1_amd64.deb Music Templates
Downloads linux-5.11.1_5.11.1-1_amd64.changes linux-5.11.1_5.11.1.orig.tar.gz linux-image-5.11.1_5.11.1-1_amd64.deb Pictures Videos

1.5 - Installer le Noyau

Installez maintenant les paquets deb :

root@debian11:/home/trainee# dpkg -i /home/trainee/linux*.deb

Constatez la création d'un nouveau grub.cfg :

root@debian11:/home/trainee# grep 5.11.1 /boot/grub/grub.cfg
echo 'Loading Linux 5.11.1 ...'
linux /boot/vmlinuz-5.11.1 root=UUID=9887a74f-a680-4bde-8f04-db5ae9ea186e ro quiet
initrd /boot/initrd.img-5.11.1
menuentry 'Debian GNU/Linux, with Linux 5.11.1' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-5.11.1-advanced-9887a74f-a680-4bde-8f04-db5ae9ea186e' {
echo 'Loading Linux 5.11.1 ...'
linux /boot/vmlinuz-5.11.1 root=UUID=9887a74f-a680-4bde-8f04-db5ae9ea186e ro quiet
initrd /boot/initrd.img-5.11.1
menuentry 'Debian GNU/Linux, with Linux 5.11.1 (recovery mode)' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-5.11.1-recovery-9887a74f-a680-4bde-8f04-db5ae9ea186e' {
echo 'Loading Linux 5.11.1 ...'
linux /boot/vmlinuz-5.11.1 root=UUID=9887a74f-a680-4bde-8f04-db5ae9ea186e ro single
initrd /boot/initrd.img-5.11.1

1.6 - Désinstaller un Noyau

Lister les noyaux installés :

root@debian11:/home/trainee# dpkg -l | grep -i "linux-image*" | awk '{print $2}'
linux-image-5.10.0-13-amd64
linux-image-5.11.1
linux-image-amd64

Le noyau se désinstalle comme tout autre paquet :

root@debian11:/home/trainee# apt-get -y purge "linux-image-5.11.1"
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following packages will be REMOVED:
linux-image-5.11.1*
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
After this operation, 15.1 MB disk space will be freed.
(Reading database ... 118012 files and directories currently installed.)
Removing linux-image-5.11.1 (5.11.1-1) ...
update-initramfs: Deleting /boot/initrd.img-5.11.1
Generating grub configuration file ...
Found background image: /usr/share/images/desktop-base/desktop-grub.png
Found linux image: /boot/vmlinuz-5.10.0-13-amd64
Found initrd image: /boot/initrd.img-5.10.0-13-amd64
done
(Reading database ... 117967 files and directories currently installed.)
Purging configuration files for linux-image-5.11.1 (5.11.1-1) ...

Vérifiez que le fichier grub.cfg a été modifié :

root@debian11:/home/trainee# grep 5.11.1 /boot/grub/grub.cfg
root@debian11:/home/trainee#

Dernièrement, listez les noyaux disponibles :

root@debian11:/home/trainee# dpkg -l | grep -i "linux-image*" | awk '{print $2}'
linux-image-5.10.0-13-amd64
linux-image-amd64

LAB #2 - Mise à Jour du Noyau avec le Gestionnaire des Paquets

Afin d'obtenir la dernière version du noyau pré-compliée par Debian, il convient d'ajouter les dépôts unstable :

root@debian11:/home/trainee# echo "deb http://deb.debian.org/debian unstable main contrib non-free" | sudo tee -a /etc/apt/sources.list
deb http://deb.debian.org/debian unstable main contrib non-free
root@debian11:/home/trainee# echo "deb-src http://deb.debian.org/debian unstable main contrib non-free" | sudo tee -a /etc/apt/sources.list
deb-src http://deb.debian.org/debian unstable main contrib non-free

Afin de ne faire que des mises à jour du noyau à partir de ce dépôt, créez le fichier /etc/apt/preferences :

root@debian11:/home/trainee# vi /etc/apt/preferences
root@debian11:/home/trainee# cat /etc/apt/preferences
Package: *
Pin: release a=bullseye
Pin-Priority: 500
Package: linux-image-amd64
Pin: release a=unstable
Pin-Priority: 1000
Package: *
Pin: release a=unstable
Pin-Priority: 100

Mettez à jour apt :

root@debian11:/home/trainee# apt update
Hit:1 http://security.debian.org/debian-security bullseye-security InRelease
Hit:2 http://deb.debian.org/debian bullseye InRelease
Get:3 http://deb.debian.org/debian bullseye-updates InRelease [39.4 kB]
Get:4 http://deb.debian.org/debian unstable InRelease [165 kB]
Get:5 http://deb.debian.org/debian unstable/contrib Sources [57.6 kB]
Get:6 http://deb.debian.org/debian unstable/main Sources [9,700 kB]
Get:7 http://deb.debian.org/debian unstable/non-free Sources [89.6 kB]
Get:8 http://deb.debian.org/debian unstable/main amd64 Packages [9,154 kB]
Get:9 http://deb.debian.org/debian unstable/main Translation-en [6,780 kB]
Get:10 http://deb.debian.org/debian unstable/contrib amd64 Packages [65.4 kB]
Get:11 http://deb.debian.org/debian unstable/contrib Translation-en [55.9 kB]
Get:12 http://deb.debian.org/debian unstable/non-free amd64 Packages [112 kB]
Get:13 http://deb.debian.org/debian unstable/non-free Translation-en [103 kB]
Fetched 26.3 MB in 5s (4,955 kB/s)
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
2 packages can be upgraded. Run 'apt list --upgradable' to see them.

Installez ensuite les mises-à-jour du noyau :

root@debian11:/home/trainee# apt -y upgrade

Re-démarrez votre VM :

root@debian11:/home/trainee# reboot

Connectez-vous de nouveau à la VM et contrôlez la version du noyau :

trainee@debian11:~$ uname -a
Linux debian11 5.17.0-1-amd64 #1 SMP PREEMPT Debian 5.17.3-1 (2022-04-18) x86_64 GNU/Linux

Déconnectez-vous et re-connectez-vous directement en tant que root.

LAB #3 - Gestion des Quotas

Sous Linux il est possible de mettre en place des quotas par utilisateur et par groupe. Ceci étant, Linux ne sait pas gérer des quotas par répertoire, uniquement des quotas par partition. L'administrateur met souvent des quotas en place sur l'arborescence de /home pour limiter l'espace de stockage occupé par les utilisateurs.

Commencez par vérifiez que le paquet quota est bien installé :

root@debian11:~# dpkg --get-selections | grep quota
root@debian11:~# apt -y install quota

Editez le fichier /etc/fstab en ajoutant les options usrquota et grpquota à la ligne /home :

root@debian11:~# vi /etc/fstab
root@debian11:~# cat /etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# systemd generates mount units based on this file, see systemd.mount(5).
# Please run 'systemctl daemon-reload' after making changes here.
#
# <file system> <mount point> <type> <options> <dump> <pass>
# / was on /dev/sda1 during installation
UUID=9887a74f-a680-4bde-8f04-db5ae9ea186e / ext4 errors=remount-ro 0 1
UUID=24f1821e-1d5b-4256-8ee3-c9ee6b382ddc /home ext4 defaults,usrquota,grpquota 0 0
# swap was on /dev/sda5 during installation
UUID=1f9439f5-4b19-49b1-b292-60c2c674cee9 none swap sw 0 0
/dev/sr0 /media/cdrom0 udf,iso9660 user,noauto 0 0

Démontez puis remontez /home :

root@debian11:~# umount /home
root@debian11:~# mount -a

Vérifiez ensuite que les options soient prises en compte :

root@debian11:~# cat /etc/mtab
sysfs /sys sysfs rw,nosuid,nodev,noexec,relatime 0 0
proc /proc proc rw,nosuid,nodev,noexec,relatime 0 0
udev /dev devtmpfs rw,nosuid,relatime,size=1976600k,nr_inodes=494150,mode=755,inode64 0 0
devpts /dev/pts devpts rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000 0 0
tmpfs /run tmpfs rw,nosuid,nodev,noexec,relatime,size=402384k,mode=755,inode64 0 0
/dev/sda1 / ext4 rw,relatime,errors=remount-ro 0 0
securityfs /sys/kernel/security securityfs rw,nosuid,nodev,noexec,relatime 0 0
tmpfs /dev/shm tmpfs rw,nosuid,nodev,inode64 0 0
tmpfs /run/lock tmpfs rw,nosuid,nodev,noexec,relatime,size=5120k,inode64 0 0
cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot 0 0
pstore /sys/fs/pstore pstore rw,nosuid,nodev,noexec,relatime 0 0
bpf /sys/fs/bpf bpf rw,nosuid,nodev,noexec,relatime,mode=700 0 0
systemd-1 /proc/sys/fs/binfmt_misc autofs rw,relatime,fd=29,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=13172 0 0
mqueue /dev/mqueue mqueue rw,nosuid,nodev,noexec,relatime 0 0
hugetlbfs /dev/hugepages hugetlbfs rw,relatime,pagesize=2M 0 0
tracefs /sys/kernel/tracing tracefs rw,nosuid,nodev,noexec,relatime 0 0
debugfs /sys/kernel/debug debugfs rw,nosuid,nodev,noexec,relatime 0 0
configfs /sys/kernel/config configfs rw,nosuid,nodev,noexec,relatime 0 0
fusectl /sys/fs/fuse/connections fusectl rw,nosuid,nodev,noexec,relatime 0 0
tmpfs /run/user/0 tmpfs rw,nosuid,nodev,relatime,size=402380k,nr_inodes=100595,mode=700,inode64 0 0
/dev/sdb1 /home ext4 rw,relatime,quota,usrquota,grpquota 0 0

3.1 - La Commande quotacheck

Pour activer les quotas sur /home, il convient d'utiliser la commande quotacheck :

root@debian11:~# quotacheck -cugvm -f /dev/sdb1
quotacheck: Your kernel probably supports ext4 quota feature but you are using external quota files. Please switch your filesystem to use ext4 quota feature as external quota files on ext4 are deprecated.
quotacheck: Scanning /dev/sdb1 [/home] done
quotacheck: Cannot stat old user quota file /home/aquota.user: No such file or directory. Usage will not be subtracted.
quotacheck: Cannot stat old group quota file /home/aquota.group: No such file or directory. Usage will not be subtracted.
quotacheck: Cannot stat old user quota file /home/aquota.user: No such file or directory. Usage will not be subtracted.
quotacheck: Cannot stat old group quota file /home/aquota.group: No such file or directory. Usage will not be subtracted.
quotacheck: Checked 7199 directories and 81583 files
quotacheck: Old file not found.
quotacheck: Old file not found.

Les options de la commande quotacheck sont :

root@debian11:~# quotacheck --help
Utility for checking and repairing quota files.
quotacheck [-gucbfinvdmMR] [-F <quota-format>] filesystem|-a
-u, --user check user files
-g, --group check group files
-c, --create-files create new quota files
-b, --backup create backups of old quota files
-f, --force force check even if quotas are enabled
-i, --interactive interactive mode
-n, --use-first-dquot use the first copy of duplicated structure
-v, --verbose print more information
-d, --debug print even more messages
-m, --no-remount do not remount filesystem read-only
-M, --try-remount try remounting filesystem read-only,
continue even if it fails
-R, --exclude-root exclude root when checking all filesystems
-F, --format=formatname check quota files of specific format
-a, --all check all filesystems
-h, --help display this message and exit
-V, --version display version information and exit
Bugs to jack@suse.cz

Les quotas ont été activés et les fichier aquota.user et aquota.group ont été créés dans le répertoire /home :

root@debian11:~# ls -la /home
total 44
drwxr-xr-x 4 root root 4096 May 1 18:05 .
drwxr-xr-x 20 root root 4096 May 1 17:41 ..
-rw------- 1 root root 7168 May 1 18:05 aquota.group
-rw------- 1 root root 7168 May 1 18:05 aquota.user
drwx------ 2 root root 16384 May 1 15:31 lost+found
drwxr-xr-x 15 trainee trainee 4096 May 1 16:28 trainee

Créez maintenant un utilisateur fenestros avec le mot de passe fenestros :

root@debian11:~# groupadd fenestros && useradd -m fenestros -c FenestrOs -d /home/fenestros -g fenestros -s /bin/bash
root@debian11:~# passwd fenestros
New password: fenestros
Retype new password: fenestros
passwd: password updated successfully

3.2 - La Commande edquota

Mettez en place maintenant un quota de 10Mo pour l'utilisateur fenestros :

root@debian8:~# EDITOR=/usr/bin/vi
root@debian8:~# export EDITOR
root@debian8:~# edquota -u fenestros -f /home

L'éditeur vi se lance et vous obtiendrez un résultat similaire à celui-ci :

Disk quotas for user fenestros (uid 1001):
Filesystem blocks soft hard inodes soft hard
/dev/sdb1 0 0 0 0 0 0

Modifiez ce fichier ainsi :

Disk quotas for user fenestros (uid 1001):
Filesystem blocks soft hard inodes soft hard
/dev/sdb1 0 8000 10000 0 0 0

Les options de la commande edquota sont :

root@debian11:~# edquota --help
edquota: Usage:
edquota [-rm] [-u] [-F formatname] [-p username] [-f filesystem] username ...
edquota [-rm] -g [-F formatname] [-p groupname] [-f filesystem] groupname ...
edquota [-rm] -P [-F formatname] [-p projectname] [-f filesystem] projectname ...
edquota [-u|g|-P] [-F formatname] [-f filesystem] -t
edquota [-u|g|-P] [-F formatname] [-f filesystem] -T username|groupname|projectname ...
-u, --user edit user data
-g, --group edit group data
-P, --project edit project data
-r, --remote edit remote quota (via RPC)
-m, --no-mixed-pathnames trim leading slashes from NFSv4 mountpoints
-F, --format=formatname edit quotas of a specific format
-p, --prototype=name copy data from a prototype user/group
--always-resolve always try to resolve name, even if it is
composed only of digits
-f, --filesystem=filesystem edit data only on a specific filesystem
-t, --edit-period edit grace period
-T, --edit-times edit grace time of a user/group
-h, --help display this help text and exit
-V, --version display version information and exit
Bugs to: jack@suse.cz

Important - Pour mettre en place un quota par group, la procédure est similaire. Il suffit d'utiliser l'option -g de la commande edquota.

3.3 - La Commande quotaon

Appliquez maintenant les quotas :

root@debian11:~# quotaon -a

Les options de la commande quotaon sont :

root@debian11:~# quotaon --help
quotaon: Usage:
quotaon [-guPvp] [-F quotaformat] [-x state] -a
quotaon [-guPvp] [-F quotaformat] [-x state] filesys ...
-a, --all turn quotas on for all filesystems
-f, --off turn quotas off
-u, --user operate on user quotas
-g, --group operate on group quotas
-P, --project operate on project quotas
-p, --print-state print whether quotas are on or off
-x, --xfs-command=cmd perform XFS quota command
-F, --format=formatname operate on specific quota format
-v, --verbose print more messages
-h, --help display this help text and exit
-V, --version display version information and exit

De cette manière vous avez mis en place un quota souple pour fenestros de 8 000 Ko et un quota stricte de 10 000 Ko.

Quand l'utilisateur fenestros aura dépassé le quota souple, il recevra un message d'avertissement. Quand il dépasse le quota stricte, il ne pourra plus enregistrer dans /home, sauf dans le cas où il supprime des fichiers pour retomber en dessous de la limite stricte.

Il est à noter que vous pouvez soit mettre en place un quota en taille, soit mettre en place un quota basé sur le nombre d'inodes utilisés par l'utilisateur.

Important - La commande pour désactivez les quotas est quotaoff.

3.4 - La Commande repquota

Pour visualiser les quotas utilisez la commande repquota :

root@debian11:~# repquota /home
*** Report for user quotas on device /dev/sdb1
Block grace time: 7days; Inode grace time: 7days
Block limits File limits
User used soft hard grace used soft hard grace
----------------------------------------------------------------------
root -- 241004 0 0 2528 0 0
trainee -- 1409108 0 0 86253 0 0

Important - Notez que l'utilisateur fenestros ne figure pas dans la liste. Le quota n'est pas visible tant que l'utilisateur ne s'est pas connecté pour la première fois. Notez aussi les période de grâce de 7 jours.

Les options de la commande repquota sont :

root@debian11:~# repquota --help
repquota: Utility for reporting quotas.
Usage:
repquota [-vugsi] [-c|C] [-t|n] [-F quotaformat] [-O (default | xml | csv)] (-a | mntpoint)
-v, --verbose display also users/groups without any usage
-u, --user display information about users
-g, --group display information about groups
-P, --project display information about projects
-s, --human-readable[=units] display numbers in human friendly units (MB, GB,
...). Units can be also specified explicitely by
an optional argument in format [kgt],[kgt] where
the first character specifies space units and the
second character specifies inode units
-t, --truncate-names truncate names to 9 characters
-p, --raw-grace print grace time in seconds since epoch
-n, --no-names do not translate uid/gid to name
-i, --no-autofs avoid autofs mountpoints
-c, --cache translate big number of ids at once
-C, --no-cache translate ids one by one
-F, --format=formatname report information for specific format
-O, --output=format format output as xml or csv
-a, --all report information for all mount points with
quotas
-h, --help display this help message and exit
-V, --version display version information and exit
Bugs to jack@suse.cz

3.5 - La Commande quota

Pour visualiser les quotas d'un utilisateur spécifique, il convient d'utiliser la commande quota :

root@debian11:~# quota fenestros
Disk quotas for user fenestros (uid 1001): no limited resources used
root@debian11:~# su - fenestros
fenestros@debian11:~$ touch test
fenestros@debian11:~$ exit
logout
root@debian11:~# quota fenestros
Disk quotas for user fenestros (uid 1001):
Filesystem blocks quota limit grace files quota limit grace
/dev/sdb1 4 8000 10000 2 0 0

Les options de la commande quota sont :

root@debian11:~# quota --help
quota: Usage: quota [-guPqvswim] [-l | [-Q | -A]] [-F quotaformat]
quota [-qvswim] [-l | [-Q | -A]] [-F quotaformat] -u username ...
quota [-qvswim] [-l | [-Q | -A]] [-F quotaformat] -g groupname ...
quota [-qvswim] [-l | [-Q | -A]] [-F quotaformat] -P projectname ...
quota [-qvswugPQm] [-F quotaformat] -f filesystem ...
-u, --user display quota for user
-g, --group display quota for group
-P, --project display quota for project
-q, --quiet print more terse message
-v, --verbose print more verbose message
-s, --human-readable[=units] display numbers in human friendly units (MB, GB,
...). Units can be also specified explicitely by
an optional argument in format [kgt],[kgt] where
the first character specifies space units and the
second character specifies inode units
--always-resolve always try to translate name to id, even if it is
composed of only digits
-w, --no-wrap do not wrap long lines
-p, --raw-grace print grace time in seconds since epoch
-l, --local-only do not query NFS filesystems
-Q, --quiet-refuse do not print error message when NFS server does
not respond
-i, --no-autofs do not query autofs mountpoints
-F, --format=formatname display quota of a specific format
-f, --filesystem-list display quota information only for given
filesystems
--filesystem=path display quota information only for given
filesystem, remaining command line arguments
are still treated as user/group/project names
-A, --all-nfs display quota for all NFS mountpoints
-m, --no-mixed-pathnames trim leading slashes from NFSv4 mountpoints
--show-mntpoint show mount point of the file system in output
--hide-device do not show file system device in output
-h, --help display this help message and exit
-V, --version display version information and exit
Bugs to: jack@suse.cz

3.6 - La Commande warnquota

La commande warnquota vérifie le ou les disques et envoie un message par mail à tout utilisateur qui a dépassé la limite soft. Elle est enrègle générale appelée par un job cron. Cependant elle peut aussi est appelée d'une manière intéractive.

Les options de la commande warnquota sont :

root@debian11:~# warnquota --help
warnquota: Usage:
warnquota [-ugsid] [-F quotaformat] [-c configfile] [-q quotatabfile] [-a adminsfile] [filesystem...]
-u, --user warn users
-g, --group warn groups
-s, --human-readable[=units] display numbers in human friendly units (MB,
GB, ...). Units can be also specified
explicitely by an optional argument in format
[kgt],[kgt] where the first character specifies
space units and the second character specifies
inode units
-i, --no-autofs avoid autofs mountpoints
-d, --no-details do not send quota information itself
-F, --format=formatname use quotafiles of specific format
-c, --config=config-file non-default config file
-q, --quota-tab=quotatab-file non-default quotatab
-a, --admins-file=admins-file non-default admins file
-I, --ignore-config-errors ignore unknown statements in config file
-h, --help display this help message and exit
-V, --version display version information and exit
warnquota: Bugs to jack@suse.cz

Copyright © 2024 Hugh Norris.