Version : 2024.01
Dernière mise-à-jour : 2024/09/26 13:19
Les systèmes de démarrage antérieurs à Systemd, SysVinit et Upstart, étaient des systèmes de démarrage séquentiels.
Systemd essaie, par contre, de démarrer autant de services en parallèle que possible. Ceci est rendu possible car la majorité d'architectures matérielles modernes sont multi-cœurs. Si un service dépend d'un autre qui n'est pas encore démarré ce premier est mis en attente dans une mémoire tampon. Qui plus est, les services qui ne sont pas nécessaires au démarrage de la machine, tel cups, ne sont démarrés ultérieurement que si nécessaire. Lors de démarrage, les partitions sont montées en parallèle. Dernièrement, Systemd remplace les scripts de démarrage traditionnels avec des binaires compilés, beaucoup plus rapides que leur prédécesseurs.
Au lieu de parler de scripts de démarrage et de niveaux d'exécution, Systemd utilise la terminologie Unités (Units) et Cibles (Targets). Une Unité peut être :
Une Cible est en quelque sorte une grande étape dans le démarrage du système :
Systemd utilise des Cibles d'une manière similaire à ce que SysVinit utilise des niveaux d'exécution. Pour rendre la transition plus facile, il existe des Cibles qui “simulent” les niveaux d'exécution de SysVinit :
[root@redhat9 ~]# ls -l /usr/lib/systemd/system/runlevel* lrwxrwxrwx. 1 root root 15 Jul 18 13:00 /usr/lib/systemd/system/runlevel0.target -> poweroff.target lrwxrwxrwx. 1 root root 13 Jul 18 13:00 /usr/lib/systemd/system/runlevel1.target -> rescue.target lrwxrwxrwx. 1 root root 17 Jul 18 13:00 /usr/lib/systemd/system/runlevel2.target -> multi-user.target lrwxrwxrwx. 1 root root 17 Jul 18 13:00 /usr/lib/systemd/system/runlevel3.target -> multi-user.target lrwxrwxrwx. 1 root root 17 Jul 18 13:00 /usr/lib/systemd/system/runlevel4.target -> multi-user.target lrwxrwxrwx. 1 root root 16 Jul 18 13:00 /usr/lib/systemd/system/runlevel5.target -> graphical.target lrwxrwxrwx. 1 root root 13 Jul 18 13:00 /usr/lib/systemd/system/runlevel6.target -> reboot.target /usr/lib/systemd/system/runlevel1.target.wants: total 0 /usr/lib/systemd/system/runlevel2.target.wants: total 0 /usr/lib/systemd/system/runlevel3.target.wants: total 0 /usr/lib/systemd/system/runlevel4.target.wants: total 0 /usr/lib/systemd/system/runlevel5.target.wants: total 0
Pour visualiser la liste des Unités, il convient d'utiliser la commande systemctl avec l'option list-units :
[root@redhat9 ~]# systemctl list-units UNIT LOAD ACTIVE SUB DESCRIPTION > proc-sys-fs-binfmt_misc.automount loaded active running Arbitrary Executable File Formats File Syst> sys-devices-pci0000:00-0000:00:01.1-ata2-host2-target2:0:0-2:0:0:0-block-sr0.device loaded active plugged QEMU_DVD-ROM sys-devices-pci0000:00-0000:00:05.0-0000:01:01.0-virtio2-host0-target0:0:0-0:0:0:0-block-sda-sda1.device loaded active plugged QEMU_HARDDISK 1 sys-devices-pci0000:00-0000:00:05.0-0000:01:01.0-virtio2-host0-target0:0:0-0:0:0:0-block-sda-sda2.device loaded active plugged QEMU_HARDDISK 2 sys-devices-pci0000:00-0000:00:05.0-0000:01:01.0-virtio2-host0-target0:0:0-0:0:0:0-block-sda.device loaded active plugged QEMU_HARDDISK sys-devices-pci0000:00-0000:00:12.0-virtio1-net-ens18.device loaded active plugged Virtio network device sys-devices-platform-serial8250-tty-ttyS0.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS0 sys-devices-platform-serial8250-tty-ttyS1.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS1 sys-devices-platform-serial8250-tty-ttyS2.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS2 sys-devices-platform-serial8250-tty-ttyS3.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS3 sys-devices-virtual-block-dm\x2d0.device loaded active plugged /sys/devices/virtual/block/dm-0 sys-devices-virtual-block-dm\x2d1.device loaded active plugged /sys/devices/virtual/block/dm-1 sys-devices-virtual-misc-rfkill.device loaded active plugged /sys/devices/virtual/misc/rfkill sys-module-configfs.device loaded active plugged /sys/module/configfs sys-module-fuse.device loaded active plugged /sys/module/fuse sys-subsystem-net-devices-ens18.device loaded active plugged Virtio network device > -.mount loaded active mounted Root Mount boot.mount loaded active mounted /boot dev-hugepages.mount loaded active mounted Huge Pages File System dev-mqueue.mount loaded active mounted POSIX Message Queue File System proc-sys-fs-binfmt_misc.mount loaded active mounted Arbitrary Executable File Formats File Syst> run-credentials-systemd\x2dsysctl.service.mount loaded active mounted /run/credentials/systemd-sysctl.service run-credentials-systemd\x2dtmpfiles\x2dsetup.service.mount loaded active mounted /run/credentials/systemd-tmpfiles-setup.ser> run-credentials-systemd\x2dtmpfiles\x2dsetup\x2ddev.service.mount loaded active mounted /run/credentials/systemd-tmpfiles-setup-dev> run-user-1000.mount loaded active mounted /run/user/1000 run-user-42.mount loaded active mounted /run/user/42 sys-fs-fuse-connections.mount loaded active mounted FUSE Control File System sys-kernel-config.mount loaded active mounted Kernel Configuration File System sys-kernel-debug-tracing.mount loaded active mounted /sys/kernel/debug/tracing sys-kernel-debug.mount loaded active mounted Kernel Debug File System sys-kernel-tracing.mount loaded active mounted Kernel Trace File System > cups.path loaded active running CUPS Scheduler systemd-ask-password-plymouth.path loaded active waiting Forward Password Requests to Plymouth Direc> systemd-ask-password-wall.path loaded active waiting Forward Password Requests to Wall Directory> init.scope loaded active running System and Service Manager session-4.scope loaded active running Session 4 of User trainee lines 1-37...skipping... UNIT LOAD ACTIVE SUB DESCRIPTION proc-sys-fs-binfmt_misc.automount loaded active running Arbitrary Executable File Formats File System Automount Point sys-devices-pci0000:00-0000:00:01.1-ata2-host2-target2:0:0-2:0:0:0-block-sr0.device loaded active plugged QEMU_DVD-ROM sys-devices-pci0000:00-0000:00:05.0-0000:01:01.0-virtio2-host0-target0:0:0-0:0:0:0-block-sda-sda1.device loaded active plugged QEMU_HARDDISK 1 sys-devices-pci0000:00-0000:00:05.0-0000:01:01.0-virtio2-host0-target0:0:0-0:0:0:0-block-sda-sda2.device loaded active plugged QEMU_HARDDISK 2 sys-devices-pci0000:00-0000:00:05.0-0000:01:01.0-virtio2-host0-target0:0:0-0:0:0:0-block-sda.device loaded active plugged QEMU_HARDDISK sys-devices-pci0000:00-0000:00:12.0-virtio1-net-ens18.device loaded active plugged Virtio network device sys-devices-platform-serial8250-tty-ttyS0.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS0 sys-devices-platform-serial8250-tty-ttyS1.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS1 sys-devices-platform-serial8250-tty-ttyS2.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS2 sys-devices-platform-serial8250-tty-ttyS3.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS3 sys-devices-virtual-block-dm\x2d0.device loaded active plugged /sys/devices/virtual/block/dm-0 sys-devices-virtual-block-dm\x2d1.device loaded active plugged /sys/devices/virtual/block/dm-1 sys-devices-virtual-misc-rfkill.device loaded active plugged /sys/devices/virtual/misc/rfkill sys-module-configfs.device loaded active plugged /sys/module/configfs sys-module-fuse.device loaded active plugged /sys/module/fuse sys-subsystem-net-devices-ens18.device loaded active plugged Virtio network device -.mount loaded active mounted Root Mount boot.mount loaded active mounted /boot dev-hugepages.mount loaded active mounted Huge Pages File System dev-mqueue.mount loaded active mounted POSIX Message Queue File System proc-sys-fs-binfmt_misc.mount loaded active mounted Arbitrary Executable File Formats File System run-credentials-systemd\x2dsysctl.service.mount loaded active mounted /run/credentials/systemd-sysctl.service run-credentials-systemd\x2dtmpfiles\x2dsetup.service.mount loaded active mounted /run/credentials/systemd-tmpfiles-setup.service run-credentials-systemd\x2dtmpfiles\x2dsetup\x2ddev.service.mount loaded active mounted /run/credentials/systemd-tmpfiles-setup-dev.service run-user-1000.mount loaded active mounted /run/user/1000 run-user-42.mount loaded active mounted /run/user/42 sys-fs-fuse-connections.mount loaded active mounted FUSE Control File System sys-kernel-config.mount loaded active mounted Kernel Configuration File System sys-kernel-debug-tracing.mount loaded active mounted /sys/kernel/debug/tracing sys-kernel-debug.mount loaded active mounted Kernel Debug File System sys-kernel-tracing.mount loaded active mounted Kernel Trace File System cups.path loaded active running CUPS Scheduler systemd-ask-password-plymouth.path loaded active waiting Forward Password Requests to Plymouth Directory Watch systemd-ask-password-wall.path loaded active waiting Forward Password Requests to Wall Directory Watch init.scope loaded active running System and Service Manager session-4.scope loaded active running Session 4 of User trainee session-c1.scope loaded active running Session c1 of User gdm accounts-daemon.service loaded active running Accounts Service atd.service loaded active running Deferred execution scheduler auditd.service loaded active running Security Auditing Service avahi-daemon.service loaded active running Avahi mDNS/DNS-SD Stack colord.service loaded active running Manage, Install and Generate Color Profiles crond.service loaded active running Command Scheduler cups.service loaded active running CUPS Scheduler dbus-broker.service loaded active running D-Bus System Message Bus dracut-shutdown.service loaded active exited Restore /run/initramfs on shutdown firewalld.service loaded active running firewalld - dynamic firewall daemon gdm.service loaded active running GNOME Display Manager irqbalance.service loaded active running irqbalance daemon iscsi.service loaded active exited Login and scanning of iSCSI devices kdump.service loaded active exited Crash recovery kernel arming kmod-static-nodes.service loaded active exited Create List of Static Device Nodes libstoragemgmt.service loaded active running libstoragemgmt plug-in server daemon lvm2-monitor.service loaded active exited Monitoring of LVM2 mirrors, snapshots etc. using dmeventd or progress polling lines 1-55
Pour consulter la liste des Unités inactifs, utilisez la commande suivante :
[root@redhat9 ~]# systemctl list-units --all | grep inactive | more ● boot.automount not-found inactive dead boot.automount ● home.mount not-found inactive dead home.mount ● sysroot.mount not-found inactive dead sysroot.mount tmp.mount loaded inactive dead Temporary Directory /tmp ● var.mount not-found inactive dead var.mount systemd-ask-password-console.path loaded inactive dead Dispatch Password Requests to Console Directory Watch alsa-restore.service loaded inactive dead Save/Restore Sound Card State alsa-state.service loaded inactive dead Manage Sound Card State (restore and store) ● auto-cpufreq.service not-found inactive dead auto-cpufreq.service ● autofs.service not-found inactive dead autofs.service blk-availability.service loaded inactive dead Availability of block devices cpupower.service loaded inactive dead Configure CPU power related settings dm-event.service loaded inactive dead Device-mapper event daemon dnf-makecache.service loaded inactive dead dnf makecache dracut-cmdline.service loaded inactive dead dracut cmdline hook dracut-initqueue.service loaded inactive dead dracut initqueue hook dracut-mount.service loaded inactive dead dracut mount hook dracut-pre-mount.service loaded inactive dead dracut pre-mount hook dracut-pre-pivot.service loaded inactive dead dracut pre-pivot and cleanup hook dracut-pre-trigger.service loaded inactive dead dracut pre-trigger hook dracut-pre-udev.service loaded inactive dead dracut pre-udev hook dracut-shutdown-onfailure.service loaded inactive dead Service executing upon dracut-shutdown failure to perform cleanup ● ebtables.service not-found inactive dead ebtables.service emergency.service loaded inactive dead Emergency Shell ● fcoe.service not-found inactive dead fcoe.service getty@tty1.service loaded inactive dead Getty on tty1 initrd-cleanup.service loaded inactive dead Cleaning Up and Shutting Down Daemons initrd-parse-etc.service loaded inactive dead Mountpoints Configured in the Real Root initrd-switch-root.service loaded inactive dead Switch Root initrd-udevadm-cleanup-db.service loaded inactive dead Cleanup udev Database insights-client-boot.service loaded inactive dead Run Insights Client at boot ● ip6tables.service not-found inactive dead ip6tables.service ● ipset.service not-found inactive dead ipset.service ● iptables.service not-found inactive dead iptables.service iscsi-init.service loaded inactive dead One time configuration for iscsi.service iscsi-onboot.service loaded inactive dead Special handling of early boot iSCSI sessions iscsi-shutdown.service loaded inactive dead Logout off all iSCSI sessions on shutdown iscsi-starter.service loaded inactive dead iscsi-starter.service iscsid.service loaded inactive dead Open-iSCSI iscsiuio.service loaded inactive dead iSCSI UserSpace I/O driver ldconfig.service loaded inactive dead Rebuild Dynamic Linker Cache logrotate.service loaded inactive dead Rotate log files low-memory-monitor.service loaded inactive dead Low Memory Monitor ● lvm2-activation-early.service not-found inactive dead lvm2-activation-early.service lvm2-lvmpolld.service loaded inactive dead LVM2 poll daemon mdmonitor.service loaded inactive dead Software RAID monitoring and management microcode.service loaded inactive dead Load CPU microcode update mlocate-updatedb.service loaded inactive dead Update a database for mlocate modprobe@configfs.service loaded inactive dead Load Kernel Module configfs modprobe@drm.service loaded inactive dead Load Kernel Module drm modprobe@fuse.service loaded inactive dead Load Kernel Module fuse multipathd.service loaded inactive dead Device-Mapper Multipath Device Controller ● network.service not-found inactive dead network.service nftables.service loaded inactive dead Netfilter Tables ● nslcd.service not-found inactive dead nslcd.service --More-- [q]
Les points noirs au début de certaines lignes dans la sortie ci-dessus sont en réalité des points blancs à l'écran. Ces points impliquent que le service, la cible ou l'unité spécifié n'a pas été trouvé sur le système. Par exemple :
[root@redhat9 ~]# systemctl status network Unit network.service could not be found.
Pour consulter la liste des Unités ainsi que leurs statuts, utilisez la commande suivante :
[root@redhat9 ~]# systemctl list-unit-files | more UNIT FILE STATE PRESET proc-sys-fs-binfmt_misc.automount static - -.mount generated - boot.mount generated - dev-hugepages.mount static - dev-mqueue.mount static - proc-sys-fs-binfmt_misc.mount disabled disabled run-vmblock\x2dfuse.mount disabled disabled sys-fs-fuse-connections.mount static - sys-kernel-config.mount static - sys-kernel-debug.mount static - sys-kernel-tracing.mount static - tmp.mount disabled disabled cups.path enabled enabled insights-client-results.path disabled disabled ostree-finalize-staged.path disabled disabled systemd-ask-password-console.path static - systemd-ask-password-plymouth.path static - systemd-ask-password-wall.path static - session-4.scope transient - session-c1.scope transient - accounts-daemon.service enabled enabled alsa-restore.service static - alsa-state.service static - arp-ethers.service disabled disabled atd.service enabled enabled auditd.service enabled enabled autovt@.service alias - avahi-daemon.service enabled enabled blk-availability.service disabled disabled bluetooth.service enabled enabled bolt.service static - brltty.service disabled disabled canberra-system-bootup.service disabled disabled canberra-system-shutdown-reboot.service disabled disabled canberra-system-shutdown.service disabled disabled chrony-wait.service disabled disabled chronyd-restricted.service disabled disabled chronyd.service disabled enabled cni-dhcp.service disabled disabled cockpit-motd.service static - cockpit-wsinstance-http.service static - cockpit-wsinstance-https-factory@.service static - cockpit-wsinstance-https@.service static - cockpit.service static - colord.service static - configure-printer@.service static - console-getty.service disabled disabled container-getty@.service static - cpupower.service disabled disabled crond.service enabled enabled cups-browsed.service disabled disabled cups.service enabled enabled dbus-broker.service enabled enabled dbus-daemon.service disabled disabled --More-- [q]
Pour visualiser les Unités d'un type spécifique, il convient d'utiliser l'option -t :
[root@redhat9 ~]# systemctl list-unit-files -t mount UNIT FILE STATE PRESET -.mount generated - boot.mount generated - dev-hugepages.mount static - dev-mqueue.mount static - proc-sys-fs-binfmt_misc.mount disabled disabled run-vmblock\x2dfuse.mount disabled disabled sys-fs-fuse-connections.mount static - sys-kernel-config.mount static - sys-kernel-debug.mount static - sys-kernel-tracing.mount static - tmp.mount disabled disabled 11 unit files listed.
Dans la colonne STATE on voit les mots static et generated.
[root@redhat9 ~]# ls -l /lib/systemd/system-generators/systemd-fstab-generator -rwxr-xr-x. 1 root root 57696 Jul 18 13:01 /lib/systemd/system-generators/systemd-fstab-generator
Il existe aussi d'autres exécutables responsables de la génération d'autres fichiers :
[root@redhat9 ~]# ls -l /lib/systemd/system-generators total 396 -rwxr-xr-x. 1 root root 541 Jul 24 06:08 kdump-dep-generator.sh -rwxr-xr-x. 1 root root 15832 May 17 18:27 ostree-system-generator lrwxrwxrwx. 1 root root 31 Aug 8 10:54 podman-system-generator -> ../../../libexec/podman/quadlet -rwxr-xr-x. 1 root root 1005 Feb 19 2024 selinux-autorelabel-generator.sh -rwxr-xr-x. 1 root root 15624 Jul 18 13:01 systemd-bless-boot-generator -rwxr-xr-x. 1 root root 40920 Jul 18 13:01 systemd-cryptsetup-generator -rwxr-xr-x. 1 root root 24312 Jul 18 13:01 systemd-debug-generator -rwxr-xr-x. 1 root root 57696 Jul 18 13:01 systemd-fstab-generator -rwxr-xr-x. 1 root root 24096 Jul 18 13:01 systemd-getty-generator -rwxr-xr-x. 1 root root 36496 Jul 18 13:01 systemd-gpt-auto-generator -rwxr-xr-x. 1 root root 16096 Jul 18 13:01 systemd-hibernate-resume-generator -rwxr-xr-x. 1 root root 24240 Jul 18 13:01 systemd-integritysetup-generator -rwxr-xr-x. 1 root root 15632 Jul 18 13:01 systemd-rc-local-generator -rwxr-xr-x. 1 root root 24296 Jul 18 13:01 systemd-run-generator -rwxr-xr-x. 1 root root 15824 Jul 18 13:01 systemd-system-update-generator -rwxr-xr-x. 1 root root 36424 Jul 18 13:01 systemd-sysv-generator -rwxr-xr-x. 1 root root 36872 Jul 18 13:01 systemd-veritysetup-generator
Les options de la commande systemctl sont :
[root@redhat9 ~]# systemctl --help
systemctl [OPTIONS...] COMMAND ...
Query or send control commands to the system manager.
Unit Commands:
list-units [PATTERN...] List units currently in memory
list-automounts [PATTERN...] List automount units currently in memory,
ordered by path
list-sockets [PATTERN...] List socket units currently in memory,
ordered by address
list-timers [PATTERN...] List timer units currently in memory,
ordered by next elapse
is-active PATTERN... Check whether units are active
is-failed PATTERN... Check whether units are failed
status [PATTERN...|PID...] Show runtime status of one or more units
show [PATTERN...|JOB...] Show properties of one or more
units/jobs or the manager
cat PATTERN... Show files and drop-ins of specified units
help PATTERN...|PID... Show manual for one or more units
list-dependencies [UNIT...] Recursively show units which are required
or wanted by the units or by which those
units are required or wanted
start UNIT... Start (activate) one or more units
stop UNIT... Stop (deactivate) one or more units
reload UNIT... Reload one or more units
restart UNIT... Start or restart one or more units
try-restart UNIT... Restart one or more units if active
reload-or-restart UNIT... Reload one or more units if possible,
otherwise start or restart
try-reload-or-restart UNIT... If active, reload one or more units,
if supported, otherwise restart
isolate UNIT Start one unit and stop all others
kill UNIT... Send signal to processes of a unit
clean UNIT... Clean runtime, cache, state, logs or
configuration of unit
freeze PATTERN... Freeze execution of unit processes
thaw PATTERN... Resume execution of a frozen unit
set-property UNIT PROPERTY=VALUE... Sets one or more properties of a unit
bind UNIT PATH [PATH] Bind-mount a path from the host into a
unit's namespace
mount-image UNIT PATH [PATH [OPTS]] Mount an image from the host into a
unit's namespace
service-log-level SERVICE [LEVEL] Get/set logging threshold for service
service-log-target SERVICE [TARGET] Get/set logging target for service
reset-failed [PATTERN...] Reset failed state for all, one, or more
units
Unit File Commands:
list-unit-files [PATTERN...] List installed unit files
enable [UNIT...|PATH...] Enable one or more unit files
disable UNIT... Disable one or more unit files
reenable UNIT... Reenable one or more unit files
preset UNIT... Enable/disable one or more unit files
based on preset configuration
preset-all Enable/disable all unit files based on
preset configuration
lines 1-55
Les fichiers de configuration des Cibles et fichiers de configuration des Unités installés par des paquets se trouvent dans le répertoire /usr/lib/systemd/system :
[root@redhat9 ~]# pkg-config systemd --variable=systemdsystemunitdir /usr/lib/systemd/system
[root@redhat9 ~]# ls -l /usr/lib/systemd/system | more total 1584 -rw-r--r--. 1 root root 729 Feb 24 2022 accounts-daemon.service -rw-r--r--. 1 root root 480 Jan 16 2024 alsa-restore.service -rw-r--r--. 1 root root 465 Jan 16 2024 alsa-state.service -rw-r--r--. 1 root root 275 Aug 10 2021 arp-ethers.service -rw-r--r--. 1 root root 274 Apr 4 2022 atd.service -rw-r--r--. 1 root root 1771 Nov 8 2023 auditd.service lrwxrwxrwx. 1 root root 14 Jul 18 13:00 autovt@.service -> getty@.service -rw-r--r--. 1 root root 1044 Nov 8 2023 avahi-daemon.service -rw-r--r--. 1 root root 870 Nov 8 2023 avahi-daemon.socket -rw-r--r--. 1 root root 964 Jul 18 13:00 basic.target drwxr-xr-x. 2 root root 6 Jul 18 13:00 basic.target.wants -r--r--r--. 1 root root 384 Feb 3 2024 blk-availability.service -rw-r--r--. 1 root root 449 Oct 31 2022 blockdev@.target -rw-r--r--. 1 root root 707 Jun 14 2022 bluetooth.service -rw-r--r--. 1 root root 435 Oct 31 2022 bluetooth.target -rw-r--r--. 1 root root 642 Jan 16 2023 bolt.service -rw-r--r--. 1 root root 463 Oct 31 2022 boot-complete.target -rw-r--r--. 1 root root 217 Aug 9 2021 brltty.service -rw-r--r--. 1 root root 491 Jul 13 2023 canberra-system-bootup.service -rw-r--r--. 1 root root 509 Jul 13 2023 canberra-system-shutdown-reboot.service -rw-r--r--. 1 root root 466 Jul 13 2023 canberra-system-shutdown.service -rw-r--r--. 1 root root 1811 Jan 23 2024 chronyd-restricted.service -rw-r--r--. 1 root root 1468 Jan 23 2024 chronyd.service -rw-r--r--. 1 root root 1082 Jan 23 2024 chrony-wait.service -rw-r--r--. 1 root root 277 Jul 23 09:37 cni-dhcp.service -rw-r--r--. 1 root root 302 Dec 4 2023 cni-dhcp.socket -rw-r--r--. 1 root root 222 Apr 2 05:45 cockpit-motd.service -rw-r--r--. 1 root root 720 Apr 2 05:45 cockpit.service -rw-r--r--. 1 root root 349 Apr 2 05:45 cockpit.socket -rw-r--r--. 1 root root 221 Apr 2 05:45 cockpit-wsinstance-http.service -rw-r--r--. 1 root root 165 Apr 2 05:45 cockpit-wsinstance-https-factory@.service -rw-r--r--. 1 root root 244 Apr 2 05:45 cockpit-wsinstance-https-factory.socket -rw-r--r--. 1 root root 215 Apr 2 05:45 cockpit-wsinstance-http.socket -rw-r--r--. 1 root root 264 Apr 2 05:45 cockpit-wsinstance-https@.service -rw-r--r--. 1 root root 478 Apr 2 05:45 cockpit-wsinstance-https@.socket -rw-r--r--. 1 root root 295 Aug 9 2021 colord.service -rw-r--r--. 1 root root 154 Aug 11 2021 configure-printer@.service -rw-r--r--. 1 root root 1102 Jul 18 13:00 console-getty.service -rw-r--r--. 1 root root 1254 Jul 18 13:00 container-getty@.service -rw-r--r--. 1 root root 294 Sep 13 18:49 cpupower.service -rw-r--r--. 1 root root 371 Nov 30 2023 crond.service -rw-r--r--. 1 root root 473 Oct 31 2022 cryptsetup-pre.target -rw-r--r--. 1 root root 420 Oct 31 2022 cryptsetup.target lrwxrwxrwx. 1 root root 13 Jul 18 13:00 ctrl-alt-del.target -> reboot.target -rw-r--r--. 1 root root 234 Jan 7 2021 cups-browsed.service -rw-r--r--. 1 root root 142 Jun 19 11:00 cups.path -rw-r--r--. 1 root root 298 Jun 19 11:00 cups.service drwxr-xr-x. 2 root root 25 Sep 25 12:03 cups.service.d -rw-r--r--. 1 root root 148 Jun 19 11:00 cups.socket -rw-r--r--. 1 root root 529 Aug 23 2022 dbus-broker.service -rw-r--r--. 1 root root 560 Jun 12 2023 dbus-daemon.service lrwxrwxrwx. 1 root root 25 Jul 18 13:00 dbus-org.freedesktop.hostname1.service -> systemd-hostnamed.service lrwxrwxrwx. 1 root root 23 Jul 18 13:00 dbus-org.freedesktop.locale1.service -> systemd-localed.service lrwxrwxrwx. 1 root root 22 Jul 18 13:00 dbus-org.freedesktop.login1.service -> systemd-logind.service --More-- [q]
Certains fichiers de configuration sont créés à la volée dans le répertoire /run/systemd/system lors du runtime puis ils sont détruits quand le système n'en a plus besoin :
[root@redhat9 ~]# ls -l /run/systemd/system/ total 0
Les fichiers de configuration des Unités crées par les utilisateurs doivent être mis dans le répertoire /usr/lib/systemd/user :
[root@redhat9 ~]# pkg-config systemd --variable=systemduserunitdir /usr/lib/systemd/user
Important : De cette façon les fichiers dans /usr/lib/systemd/user surchargent les fichiers dans le répertoire /run/systemd/system qui surchargent les fichiers dans le répertoire /usr/lib/systemd/system.
Prenons le cas du service sshd qui est configuré par le fichier /usr/lib/systemd/system/sshd.service :
[root@redhat9 ~]# cat /usr/lib/systemd/system/sshd.service [Unit] Description=OpenSSH server daemon Documentation=man:sshd(8) man:sshd_config(5) After=network.target sshd-keygen.target Wants=sshd-keygen.target [Service] Type=notify EnvironmentFile=-/etc/sysconfig/sshd ExecStart=/usr/sbin/sshd -D $OPTIONS ExecReload=/bin/kill -HUP $MAINPID KillMode=process Restart=on-failure RestartSec=42s [Install] WantedBy=multi-user.target
Dans le fichier on peut noter la présence des lignes suivantes dans la section [Unit] :
Dans le fichier on peut aussi noter la présence des lignes suivantes dans la section [Service] :
Dernièrement on note la présence de la ligne suivante dans la section [Install] :
Pour consulter l'ensemble des directives de configuration ainsi que leurs valeurs d'une Unité, il convient d'utiliser la commande systemctl show en spécifiant l'Unité concernée :
[root@redhat9 ~]# systemctl show sshd
Type=notify
ExitType=main
Restart=on-failure
NotifyAccess=main
RestartUSec=42s
TimeoutStartUSec=1min 30s
TimeoutStopUSec=1min 30s
TimeoutAbortUSec=1min 30s
TimeoutStartFailureMode=terminate
TimeoutStopFailureMode=terminate
RuntimeMaxUSec=infinity
RuntimeRandomizedExtraUSec=0
WatchdogUSec=0
WatchdogTimestampMonotonic=0
RootDirectoryStartOnly=no
RemainAfterExit=no
GuessMainPID=yes
MainPID=875
ControlPID=0
FileDescriptorStoreMax=0
NFileDescriptorStore=0
StatusErrno=0
Result=success
ReloadResult=success
CleanResult=success
UID=[not set]
GID=[not set]
NRestarts=0
OOMPolicy=stop
ReloadSignal=1
ExecMainStartTimestamp=Wed 2024-09-25 12:44:53 CEST
ExecMainStartTimestampMonotonic=18089127
ExecMainExitTimestampMonotonic=0
ExecMainPID=875
ExecMainCode=0
ExecMainStatus=0
ExecStart={ path=/usr/sbin/sshd ; argv[]=/usr/sbin/sshd -D $OPTIONS ; ignore_errors=no ; start_time=[n/a] ; stop_time=[n/a] ; pid=0 ; code=(null) ; status=0/0 }
ExecStartEx={ path=/usr/sbin/sshd ; argv[]=/usr/sbin/sshd -D $OPTIONS ; flags= ; start_time=[n/a] ; stop_time=[n/a] ; pid=0 ; code=(null) ; status=0/0 }
ExecReload={ path=/bin/kill ; argv[]=/bin/kill -HUP $MAINPID ; ignore_errors=no ; start_time=[n/a] ; stop_time=[n/a] ; pid=0 ; code=(null) ; status=0/0 }
ExecReloadEx={ path=/bin/kill ; argv[]=/bin/kill -HUP $MAINPID ; flags= ; start_time=[n/a] ; stop_time=[n/a] ; pid=0 ; code=(null) ; status=0/0 }
Slice=system.slice
ControlGroup=/system.slice/sshd.service
ControlGroupId=3690
MemoryCurrent=5275648
MemoryAvailable=infinity
CPUUsageNSec=122370000
TasksCurrent=1
IPIngressBytes=[no data]
IPIngressPackets=[no data]
IPEgressBytes=[no data]
IPEgressPackets=[no data]
IOReadBytes=18446744073709551615
IOReadOperations=18446744073709551615
IOWriteBytes=18446744073709551615
IOWriteOperations=18446744073709551615
lines 1-55
Pour consulter la liste des dépendances d'une Unité, il convient d'utiliser systemctl list-dependancies en spécifiant l'Unité concernée :
[root@redhat9 ~]# systemctl list-dependencies sshd.service sshd.service ● ├─system.slice ● ├─sshd-keygen.target ○ │ ├─sshd-keygen@ecdsa.service ○ │ ├─sshd-keygen@ed25519.service ○ │ └─sshd-keygen@rsa.service ● └─sysinit.target ● ├─dev-hugepages.mount ● ├─dev-mqueue.mount ● ├─dracut-shutdown.service ○ ├─iscsi-onboot.service ○ ├─iscsi-starter.service ● ├─kmod-static-nodes.service ○ ├─ldconfig.service ● ├─lvm2-lvmpolld.socket ● ├─lvm2-monitor.service ○ ├─multipathd.service ● ├─nis-domainname.service ● ├─plymouth-read-write.service ● ├─plymouth-start.service ● ├─proc-sys-fs-binfmt_misc.automount ○ ├─selinux-autorelabel-mark.service ● ├─sys-fs-fuse-connections.mount ● ├─sys-kernel-config.mount ● ├─sys-kernel-debug.mount ● ├─sys-kernel-tracing.mount ○ ├─systemd-ask-password-console.path ○ ├─systemd-binfmt.service ○ ├─systemd-boot-random-seed.service ● ├─systemd-boot-update.service ○ ├─systemd-firstboot.service ○ ├─systemd-hwdb-update.service ○ ├─systemd-journal-catalog-update.service ● ├─systemd-journal-flush.service ● ├─systemd-journald.service ○ ├─systemd-machine-id-commit.service ● ├─systemd-modules-load.service ● ├─systemd-network-generator.service ○ ├─systemd-pcrmachine.service ○ ├─systemd-pcrphase-sysinit.service ○ ├─systemd-pcrphase.service ● ├─systemd-random-seed.service ○ ├─systemd-repart.service ● ├─systemd-sysctl.service ○ ├─systemd-sysusers.service ● ├─systemd-tmpfiles-setup-dev.service ● ├─systemd-tmpfiles-setup.service ● ├─systemd-udev-trigger.service ● ├─systemd-udevd.service ○ ├─systemd-update-done.service ● ├─systemd-update-utmp.service ● ├─cryptsetup.target ● ├─integritysetup.target ● ├─local-fs.target ● │ ├─-.mount lines 1-55
Les fichiers de configuration par défaut peuvent aussi être surchargés par des fichiers dans d'autres répertoires :
[root@redhat9 ~]# pkg-config systemd --variable=systemdsystemunitpath /etc/systemd/system:/etc/systemd/system:/run/systemd/system:/usr/local/lib/systemd/system:/usr/lib/systemd/system:/usr/lib/systemd/system:/lib/systemd/system
[root@redhat9 ~]# ls -l /etc/systemd/system total 8 drwxr-xr-x. 2 root root 65 Oct 19 2023 basic.target.wants drwxr-xr-x. 2 root root 31 Oct 19 2023 bluetooth.target.wants lrwxrwxrwx. 1 root root 37 Oct 19 2023 ctrl-alt-del.target -> /usr/lib/systemd/system/reboot.target lrwxrwxrwx. 1 root root 41 Oct 19 2023 dbus-org.bluez.service -> /usr/lib/systemd/system/bluetooth.service lrwxrwxrwx. 1 root root 41 Oct 19 2023 dbus-org.fedoraproject.FirewallD1.service -> /usr/lib/systemd/system/firewalld.service lrwxrwxrwx. 1 root root 44 Oct 19 2023 dbus-org.freedesktop.Avahi.service -> /usr/lib/systemd/system/avahi-daemon.service lrwxrwxrwx. 1 root root 44 Oct 19 2023 dbus-org.freedesktop.ModemManager1.service -> /usr/lib/systemd/system/ModemManager.service lrwxrwxrwx. 1 root root 57 Oct 19 2023 dbus-org.freedesktop.nm-dispatcher.service -> /usr/lib/systemd/system/NetworkManager-dispatcher.service lrwxrwxrwx. 1 root root 43 Oct 19 2023 dbus.service -> /usr/lib/systemd/system/dbus-broker.service lrwxrwxrwx. 1 root root 40 Oct 19 2023 default.target -> /usr/lib/systemd/system/graphical.target drwxr-xr-x. 2 root root 45 Oct 19 2023 default.target.wants drwxr-xr-x. 2 root root 38 Oct 19 2023 'dev-virtio\x2dports-org.qemu.guest_agent.0.device.wants' lrwxrwxrwx. 1 root root 35 Oct 19 2023 display-manager.service -> /usr/lib/systemd/system/gdm.service drwxr-xr-x. 2 root root 32 Oct 19 2023 getty.target.wants drwxr-xr-x. 2 root root 181 Oct 19 2023 graphical.target.wants drwxr-xr-x. 2 root root 36 Oct 19 2023 local-fs.target.wants drwxr-xr-x. 2 root root 4096 Oct 19 2023 multi-user.target.wants drwxr-xr-x. 2 root root 48 Oct 19 2023 network-online.target.wants drwxr-xr-x. 2 root root 26 Oct 19 2023 printer.target.wants drwxr-xr-x. 2 root root 27 Oct 19 2023 remote-fs.target.wants drwxr-xr-x. 2 root root 186 Oct 19 2023 sockets.target.wants drwxr-xr-x. 2 root root 4096 Sep 25 12:08 sysinit.target.wants drwxr-xr-x. 2 root root 86 Oct 19 2023 timers.target.wants drwxr-xr-x. 2 root root 29 Oct 19 2023 vmtoolsd.service.requires
Pour avoir une évaluation du temps de démarrage, il convient d'utiliser la commande suivante :
[root@redhat9 ~]# systemd-analyze Startup finished in 1.309s (kernel) + 4.384s (initrd) + 29.375s (userspace) = 35.069s graphical.target reached after 29.358s in userspace.
L'option blame de la commande systemd-analyze permet de voir le temps de démarrage de chaque Unité afin de pourvoir se concentrer sur les plus lentes :
[root@redhat9 ~]# systemd-analyze blame 15.289s plymouth-quit-wait.service 8.760s dev-disk-by\x2dpartuuid-d00dfc8a\x2d02.device 8.760s dev-disk-by\x2did-scsi\x2d0QEMU_QEMU_HARDDISK_drive\x2dscsi0\x2dpart2.device 8.760s sys-devices-pci0000:00-0000:00:05.0-0000:01:01.0-virtio2-host0-target0:0:0-0:0:0:0-block-sda-sda2.device 8.760s dev-disk-by\x2dpath-pci\x2d0000:01:01.0\x2dscsi\x2d0:0:0:0\x2dpart2.device 8.760s dev-sda2.device 8.662s sys-devices-pci0000:00-0000:00:05.0-0000:01:01.0-virtio2-host0-target0:0:0-0:0:0:0-block-sda-sda1.device 8.662s dev-disk-by\x2did-scsi\x2d0QEMU_QEMU_HARDDISK_drive\x2dscsi0\x2dpart1.device 8.662s dev-sda1.device 8.662s dev-disk-by\x2dpath-pci\x2d0000:01:01.0\x2dscsi\x2d0:0:0:0\x2dpart1.device 8.662s dev-disk-by\x2duuid-6f6c5bb9\x2d30be\x2d4734\x2dbc23\x2d03fed8541616.device 8.662s dev-disk-by\x2dpartuuid-d00dfc8a\x2d01.device 8.629s dev-sda.device 8.629s dev-disk-by\x2dpath-pci\x2d0000:01:01.0\x2dscsi\x2d0:0:0:0.device 8.629s dev-disk-by\x2did-scsi\x2d0QEMU_QEMU_HARDDISK_drive\x2dscsi0.device 8.629s sys-devices-pci0000:00-0000:00:05.0-0000:01:01.0-virtio2-host0-target0:0:0-0:0:0:0-block-sda.device 8.629s dev-disk-by\x2ddiskseq-1.device 8.589s sys-module-fuse.device 8.578s sys-devices-pci0000:00-0000:00:12.0-virtio1-net-ens18.device 8.578s sys-subsystem-net-devices-ens18.device 8.560s sys-devices-platform-serial8250-tty-ttyS0.device 8.560s dev-ttyS0.device 8.559s sys-devices-platform-serial8250-tty-ttyS2.device 8.559s dev-ttyS2.device 8.558s dev-ttyS1.device 8.558s sys-devices-platform-serial8250-tty-ttyS1.device 8.557s dev-ttyS3.device 8.557s sys-devices-platform-serial8250-tty-ttyS3.device 8.510s sys-module-configfs.device 4.024s initrd-switch-root.service 2.468s firewalld.service 2.157s kdump.service 1.944s systemd-udev-settle.service 1.548s dnf-makecache.service 1.454s NetworkManager-wait-online.service 1.309s udisks2.service 1.294s NetworkManager.service 1.112s power-profiles-daemon.service 1.091s polkit.service 1.015s accounts-daemon.service 953ms ModemManager.service 900ms user@42.service 888ms dracut-initqueue.service 671ms dbus-broker.service 661ms systemd-tmpfiles-setup-dev.service 658ms systemd-udevd.service 561ms lvm2-monitor.service 547ms boot.mount 506ms cups.service 464ms sshd.service 446ms logrotate.service 382ms systemd-random-seed.service 376ms auditd.service 371ms systemd-tmpfiles-setup.service 324ms systemd-sysctl.service lines 1-55
L'option critical-chain de la commande systemd-analyze permet de voir l'enchaînement des événements qui amènent au chargement de l'Unité qui est passée en argument :
[root@redhat9 ~]# systemd-analyze critical-chain sshd.service
The time when unit became active or started is printed after the "@" character.
The time the unit took to start is printed after the "+" character.
sshd.service +464ms
└─network.target @12.377s
└─wpa_supplicant.service @25.556s +119ms
└─basic.target @7.432s
└─dbus-broker.service @6.758s +671ms
└─dbus.socket @6.741s
└─sysinit.target @6.737s
└─systemd-update-utmp.service @6.721s +15ms
└─auditd.service @6.333s +376ms
└─systemd-tmpfiles-setup.service @5.951s +371ms
└─local-fs.target @5.939s
└─run-user-42.mount @14.616s
└─local-fs-pre.target @5.379s
└─systemd-tmpfiles-setup-dev.service @3.398s +661ms
└─kmod-static-nodes.service @3.243s +49ms
└─systemd-journald.socket
└─system.slice
└─-.slice
Les options de la commande systemd-analyze sont :
[root@redhat9 ~]# systemd-analyze --help
systemd-analyze [OPTIONS...] COMMAND ...
Profile systemd, show unit dependencies, check unit files.
Commands:
[time] Print time required to boot the machine
blame Print list of running units ordered by
time to init
critical-chain [UNIT...] Print a tree of the time critical chain
of units
plot Output SVG graphic showing service
initialization
dot [UNIT...] Output dependency graph in dot(1) format
dump [PATTERN...] Output state serialization of service
manager
cat-config Show configuration file and drop-ins
unit-files List files and symlinks for units
unit-paths List load directories for units
exit-status [STATUS...] List exit status definitions
capability [CAP...] List capability definitions
syscall-filter [NAME...] List syscalls in seccomp filters
filesystems [NAME...] List known filesystems
condition CONDITION... Evaluate conditions and asserts
compare-versions VERSION1 [OP] VERSION2
Compare two version strings
verify FILE... Check unit files for correctness
calendar SPEC... Validate repetitive calendar time
events
timestamp TIMESTAMP... Validate a timestamp
timespan SPAN... Validate a time span
security [UNIT...] Analyze security of unit
inspect-elf FILE... Parse and print ELF package metadata
Options:
--recursive-errors=MODE Control which units are verified
--offline=BOOL Perform a security review on unit file(s)
--threshold=N Exit with a non-zero status when overall
exposure level is over threshold value
--security-policy=PATH Use custom JSON security policy instead
of built-in one
--json=pretty|short|off Generate JSON output of the security
analysis table, or plot's raw time data
--no-pager Do not pipe output into a pager
--no-legend Disable column headers and hints in plot
with either --table or --json=
--system Operate on system systemd instance
--user Operate on user systemd instance
--global Operate on global user configuration
-H --host=[USER@]HOST Operate on remote host
-M --machine=CONTAINER Operate on local container
--order Show only order in the graph
--require Show only requirement in the graph
--from-pattern=GLOB Show only origins in the graph
--to-pattern=GLOB Show only destinations in the graph
--fuzz=SECONDS Also print services which finished SECONDS
lines 1-55
Chaque Cible est décrite par un fichier de configuration :
[root@redhat9 ~]# cat /usr/lib/systemd/system/graphical.target # SPDX-License-Identifier: LGPL-2.1-or-later # # This file is part of systemd. # # systemd is free software; you can redistribute it and/or modify it # under the terms of the GNU Lesser General Public License as published by # the Free Software Foundation; either version 2.1 of the License, or # (at your option) any later version. [Unit] Description=Graphical Interface Documentation=man:systemd.special(7) Requires=multi-user.target Wants=display-manager.service Conflicts=rescue.service rescue.target After=multi-user.target rescue.service rescue.target display-manager.service AllowIsolate=yes
Dans ce fichier on peut noter la présence des lignes suivantes :
Les dépendances d'une Cible peuvent être consultées en utilisant la commande systemctl list-dependencies :
[root@redhat9 ~]# systemctl list-dependencies multi-user.target multi-user.target ● ├─atd.service ● ├─auditd.service ● ├─avahi-daemon.service ● ├─crond.service ● ├─cups.path ● ├─cups.service ● ├─firewalld.service ○ ├─insights-client-boot.service ● ├─irqbalance.service ● ├─kdump.service ● ├─libstoragemgmt.service ● ├─mcelog.service ○ ├─mdmonitor.service ● ├─ModemManager.service ● ├─NetworkManager.service ○ ├─ostree-readonly-sysroot-migration.service ● ├─plymouth-quit-wait.service ○ ├─plymouth-quit.service ● ├─rhsmcertd.service ● ├─rsyslog.service ○ ├─smartd.service ● ├─sshd.service ○ ├─sssd.service ● ├─systemd-ask-password-wall.path ● ├─systemd-logind.service ○ ├─systemd-update-utmp-runlevel.service ● ├─systemd-user-sessions.service ○ ├─tuned.service ○ ├─vmtoolsd.service ● ├─basic.target ● │ ├─-.mount ○ │ ├─low-memory-monitor.service ○ │ ├─microcode.service ● │ ├─paths.target ● │ ├─slices.target ● │ │ ├─-.slice ● │ │ └─system.slice ● │ ├─sockets.target ● │ │ ├─avahi-daemon.socket ● │ │ ├─cups.socket ● │ │ ├─dbus.socket ● │ │ ├─dm-event.socket ● │ │ ├─iscsid.socket ● │ │ ├─iscsiuio.socket ○ │ │ ├─multipathd.socket ● │ │ ├─sssd-kcm.socket ● │ │ ├─systemd-coredump.socket ● │ │ ├─systemd-initctl.socket ● │ │ ├─systemd-journald-dev-log.socket ● │ │ ├─systemd-journald.socket ● │ │ ├─systemd-udevd-control.socket ● │ │ └─systemd-udevd-kernel.socket ● │ ├─sysinit.target ● │ │ ├─dev-hugepages.mount lines 1-55
Les points noirs au début de chaque ligne dans la sortie ci-dessus peuvent être de trois couleurs différentes :
Pour visualiser les Unités en état d'erreur fatale, utilisez la commande systemctl –failed :
[root@redhat9 ~]# systemctl --failed UNIT LOAD ACTIVE SUB DESCRIPTION 0 loaded units listed.
Les dépendances sont créés sous la forme de liens symboliques dans les répertoires /etc/systemd/system/multi-user.target.wants et /usr/lib/systemd/system/multi-user.target.wants :
[root@redhat9 ~]# ls -l /etc/systemd/system/multi-user.target.wants total 0 lrwxrwxrwx. 1 root root 35 Oct 19 2023 atd.service -> /usr/lib/systemd/system/atd.service lrwxrwxrwx. 1 root root 38 Oct 19 2023 auditd.service -> /usr/lib/systemd/system/auditd.service lrwxrwxrwx. 1 root root 44 Oct 19 2023 avahi-daemon.service -> /usr/lib/systemd/system/avahi-daemon.service lrwxrwxrwx. 1 root root 37 Oct 19 2023 crond.service -> /usr/lib/systemd/system/crond.service lrwxrwxrwx. 1 root root 33 Oct 19 2023 cups.path -> /usr/lib/systemd/system/cups.path lrwxrwxrwx. 1 root root 36 Oct 19 2023 cups.service -> /usr/lib/systemd/system/cups.service lrwxrwxrwx. 1 root root 41 Oct 19 2023 firewalld.service -> /usr/lib/systemd/system/firewalld.service lrwxrwxrwx. 1 root root 52 Oct 19 2023 insights-client-boot.service -> /usr/lib/systemd/system/insights-client-boot.service lrwxrwxrwx. 1 root root 42 Oct 19 2023 irqbalance.service -> /usr/lib/systemd/system/irqbalance.service lrwxrwxrwx. 1 root root 37 Oct 19 2023 kdump.service -> /usr/lib/systemd/system/kdump.service lrwxrwxrwx. 1 root root 46 Oct 19 2023 libstoragemgmt.service -> /usr/lib/systemd/system/libstoragemgmt.service lrwxrwxrwx. 1 root root 38 Oct 19 2023 mcelog.service -> /usr/lib/systemd/system/mcelog.service lrwxrwxrwx. 1 root root 41 Oct 19 2023 mdmonitor.service -> /usr/lib/systemd/system/mdmonitor.service lrwxrwxrwx. 1 root root 44 Oct 19 2023 ModemManager.service -> /usr/lib/systemd/system/ModemManager.service lrwxrwxrwx. 1 root root 46 Oct 19 2023 NetworkManager.service -> /usr/lib/systemd/system/NetworkManager.service lrwxrwxrwx. 1 root root 40 Oct 19 2023 remote-fs.target -> /usr/lib/systemd/system/remote-fs.target lrwxrwxrwx. 1 root root 41 Oct 19 2023 rhsmcertd.service -> /usr/lib/systemd/system/rhsmcertd.service lrwxrwxrwx. 1 root root 39 Oct 19 2023 rsyslog.service -> /usr/lib/systemd/system/rsyslog.service lrwxrwxrwx. 1 root root 38 Oct 19 2023 smartd.service -> /usr/lib/systemd/system/smartd.service lrwxrwxrwx. 1 root root 36 Oct 19 2023 sshd.service -> /usr/lib/systemd/system/sshd.service lrwxrwxrwx. 1 root root 36 Oct 19 2023 sssd.service -> /usr/lib/systemd/system/sssd.service lrwxrwxrwx. 1 root root 37 Oct 19 2023 tuned.service -> /usr/lib/systemd/system/tuned.service lrwxrwxrwx. 1 root root 40 Oct 19 2023 vmtoolsd.service -> /usr/lib/systemd/system/vmtoolsd.service [root@redhat9 ~]# ls -l /usr/lib/systemd/system/multi-user.target.wants total 0 lrwxrwxrwx. 1 root root 15 Jul 18 13:00 getty.target -> ../getty.target lrwxrwxrwx. 1 root root 44 May 17 18:27 ostree-readonly-sysroot-migration.service -> ../ostree-readonly-sysroot-migration.service lrwxrwxrwx. 1 root root 24 Jul 14 2023 plymouth-quit.service -> ../plymouth-quit.service lrwxrwxrwx. 1 root root 29 Jul 14 2023 plymouth-quit-wait.service -> ../plymouth-quit-wait.service lrwxrwxrwx. 1 root root 33 Jul 18 13:00 systemd-ask-password-wall.path -> ../systemd-ask-password-wall.path lrwxrwxrwx. 1 root root 25 Jul 18 13:00 systemd-logind.service -> ../systemd-logind.service lrwxrwxrwx. 1 root root 39 Jul 18 13:00 systemd-update-utmp-runlevel.service -> ../systemd-update-utmp-runlevel.service lrwxrwxrwx. 1 root root 32 Jul 18 13:00 systemd-user-sessions.service -> ../systemd-user-sessions.service
Pour consulter la cible par défaut, il convient d'utiliser la commande systemctl get-default :
[root@redhat9 ~]# systemctl get-default graphical.target
La Cible par défaut est représentée par le lien symbolique /etc/systemd/system/default.target :
[root@redhat9 ~]# ls -l /etc/systemd/system/default.target lrwxrwxrwx. 1 root root 40 Oct 19 2023 /etc/systemd/system/default.target -> /usr/lib/systemd/system/graphical.target
Pour modifier la Cible par défaut avec une prise en compte lors du prochain démarrage, il convient d'utiliser la commande systemctl set-default :
[root@redhat9 ~]# systemctl set-default multi-user.target Removed "/etc/systemd/system/default.target". Created symlink /etc/systemd/system/default.target → /usr/lib/systemd/system/multi-user.target. [root@redhat9 ~]# ls -l /etc/systemd/system/default.target lrwxrwxrwx. 1 root root 41 Sep 26 14:50 /etc/systemd/system/default.target -> /usr/lib/systemd/system/multi-user.target [root@redhat9 ~]# systemctl set-default graphical.target Removed "/etc/systemd/system/default.target". Created symlink /etc/systemd/system/default.target → /usr/lib/systemd/system/graphical.target. [root@redhat9 ~]# ls -l /etc/systemd/system/default.target lrwxrwxrwx. 1 root root 40 Sep 26 14:51 /etc/systemd/system/default.target -> /usr/lib/systemd/system/graphical.target
Il est possible de modifier la cible actuellement en cours en utilisant la commande systemctl isolate :
[root@redhat9 ~]# systemctl isolate rescue
[root@redhat9 ~]# systemctl list-units --type target | egrep "eme|res|gra|mul" | head -1
rescue.target loaded active active Rescue Mode
[root@redhat9 ~]# runlevel
5 1
[root@redhat9 ~]# who -r
run-level 1 2024-09-26 14:52 last=5
[root@redhat9 ~]# systemctl isolate graphical
[root@redhat9 ~]# systemctl list-units --type target | egrep "eme|res|gra|mul" | head -1
graphical.target loaded active active Graphical Interface
[root@redhat9 ~]# runlevel
1 5
[root@redhat9 ~]# who -r
run-level 5 2024-09-26 14:55 last=1
Commencez par installer le paquet httpd :
[root@redhat9 ~]# dnf install httpd Updating Subscription Management repositories. Last metadata expiration check: 1:59:56 ago on Thu 26 Sep 2024 12:57:02 PM CEST. Dependencies resolved. ================================================================================================================================================================================================================== Package Architecture Version Repository Size ================================================================================================================================================================================================================== Installing: httpd x86_64 2.4.57-11.el9_4.1 rhel-9-for-x86_64-appstream-rpms 51 k Installing dependencies: apr x86_64 1.7.0-12.el9_3 rhel-9-for-x86_64-appstream-rpms 126 k apr-util x86_64 1.6.1-23.el9 rhel-9-for-x86_64-appstream-rpms 97 k apr-util-bdb x86_64 1.6.1-23.el9 rhel-9-for-x86_64-appstream-rpms 14 k httpd-core x86_64 2.4.57-11.el9_4.1 rhel-9-for-x86_64-appstream-rpms 1.5 M httpd-filesystem noarch 2.4.57-11.el9_4.1 rhel-9-for-x86_64-appstream-rpms 14 k httpd-tools x86_64 2.4.57-11.el9_4.1 rhel-9-for-x86_64-appstream-rpms 86 k redhat-logos-httpd noarch 90.4-2.el9 rhel-9-for-x86_64-appstream-rpms 18 k Installing weak dependencies: apr-util-openssl x86_64 1.6.1-23.el9 rhel-9-for-x86_64-appstream-rpms 17 k mod_http2 x86_64 2.0.26-2.el9_4 rhel-9-for-x86_64-appstream-rpms 167 k mod_lua x86_64 2.4.57-11.el9_4.1 rhel-9-for-x86_64-appstream-rpms 60 k Transaction Summary ================================================================================================================================================================================================================== Install 11 Packages Total download size: 2.2 M Installed size: 6.0 M Is this ok [y/N]: y Downloading Packages: (1/11): apr-util-bdb-1.6.1-23.el9.x86_64.rpm 28 kB/s | 14 kB 00:00 (2/11): apr-util-openssl-1.6.1-23.el9.x86_64.rpm 31 kB/s | 17 kB 00:00 (3/11): apr-util-1.6.1-23.el9.x86_64.rpm 165 kB/s | 97 kB 00:00 (4/11): redhat-logos-httpd-90.4-2.el9.noarch.rpm 69 kB/s | 18 kB 00:00 (5/11): apr-1.7.0-12.el9_3.x86_64.rpm 374 kB/s | 126 kB 00:00 (6/11): mod_http2-2.0.26-2.el9_4.x86_64.rpm 435 kB/s | 167 kB 00:00 (7/11): httpd-core-2.4.57-11.el9_4.1.x86_64.rpm 2.9 MB/s | 1.5 MB 00:00 (8/11): httpd-filesystem-2.4.57-11.el9_4.1.noarch.rpm 31 kB/s | 14 kB 00:00 (9/11): httpd-2.4.57-11.el9_4.1.x86_64.rpm 63 kB/s | 51 kB 00:00 (10/11): httpd-tools-2.4.57-11.el9_4.1.x86_64.rpm 297 kB/s | 86 kB 00:00 (11/11): mod_lua-2.4.57-11.el9_4.1.x86_64.rpm 154 kB/s | 60 kB 00:00 ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Total 1.2 MB/s | 2.2 MB 00:01 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : apr-1.7.0-12.el9_3.x86_64 1/11 Installing : apr-util-bdb-1.6.1-23.el9.x86_64 2/11 Installing : apr-util-openssl-1.6.1-23.el9.x86_64 3/11 Installing : apr-util-1.6.1-23.el9.x86_64 4/11 Installing : httpd-tools-2.4.57-11.el9_4.1.x86_64 5/11 Running scriptlet: httpd-filesystem-2.4.57-11.el9_4.1.noarch 6/11 Installing : httpd-filesystem-2.4.57-11.el9_4.1.noarch 6/11 Installing : httpd-core-2.4.57-11.el9_4.1.x86_64 7/11 Installing : mod_lua-2.4.57-11.el9_4.1.x86_64 8/11 Installing : redhat-logos-httpd-90.4-2.el9.noarch 9/11 Installing : mod_http2-2.0.26-2.el9_4.x86_64 10/11 Installing : httpd-2.4.57-11.el9_4.1.x86_64 11/11 Running scriptlet: httpd-2.4.57-11.el9_4.1.x86_64 11/11 Verifying : apr-util-1.6.1-23.el9.x86_64 1/11 Verifying : apr-util-bdb-1.6.1-23.el9.x86_64 2/11 Verifying : apr-util-openssl-1.6.1-23.el9.x86_64 3/11 Verifying : redhat-logos-httpd-90.4-2.el9.noarch 4/11 Verifying : apr-1.7.0-12.el9_3.x86_64 5/11 Verifying : mod_http2-2.0.26-2.el9_4.x86_64 6/11 Verifying : httpd-2.4.57-11.el9_4.1.x86_64 7/11 Verifying : httpd-core-2.4.57-11.el9_4.1.x86_64 8/11 Verifying : httpd-filesystem-2.4.57-11.el9_4.1.noarch 9/11 Verifying : httpd-tools-2.4.57-11.el9_4.1.x86_64 10/11 Verifying : mod_lua-2.4.57-11.el9_4.1.x86_64 11/11 Installed products updated. Installed: apr-1.7.0-12.el9_3.x86_64 apr-util-1.6.1-23.el9.x86_64 apr-util-bdb-1.6.1-23.el9.x86_64 apr-util-openssl-1.6.1-23.el9.x86_64 httpd-2.4.57-11.el9_4.1.x86_64 httpd-core-2.4.57-11.el9_4.1.x86_64 httpd-filesystem-2.4.57-11.el9_4.1.noarch httpd-tools-2.4.57-11.el9_4.1.x86_64 mod_http2-2.0.26-2.el9_4.x86_64 mod_lua-2.4.57-11.el9_4.1.x86_64 redhat-logos-httpd-90.4-2.el9.noarch Complete!
Pour obtenir le détail sur un service donné, il convient d'utiliser la commande systemctl status :
[root@redhat9 ~]# systemctl status httpd.service
○ httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled; preset: disabled)
Active: inactive (dead)
Docs: man:httpd.service(8)
Dans le cas du service httpd ci-dessus, on peut constater que le statut est disabled. Le statut peut être une de 2 valeurs :
Il est possible de vérifier le statut en utilisant le commande systemctl is-enabled :
[root@redhat9 ~]# systemctl is-enabled httpd.service disabled
Pour rendre le statut enabled, il convient d'utiliser la commande systemctl enable :
[root@redhat9 ~]# systemctl enable httpd.service
Created symlink /etc/systemd/system/multi-user.target.wants/httpd.service → /usr/lib/systemd/system/httpd.service.
[root@redhat9 ~]# systemctl is-enabled httpd.service
enabled
[root@redhat9 ~]# systemctl status httpd.service
○ httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; preset: disabled)
Active: inactive (dead)
Docs: man:httpd.service(8)
Dans le cas du service httpd ci-dessus, on peut maintenant constater que l'état est inactive (dead). L'état peut être une de 7 valeurs :
Il est possible de vérifier l'état en utilisant le commande systemctl is-active :
[root@redhat9 ~]# systemctl is-active httpd.service inactive
Pour rendre l'état active(running), utilisez la commande suivante :
[root@redhat9 ~]# systemctl start httpd.service
Vérifiez ensuite l'état du service :
[root@redhat9 ~]# systemctl is-active httpd.service
active
[root@redhat9 ~]# systemctl status httpd.service
● httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; preset: disabled)
Active: active (running) since Thu 2024-09-26 15:01:28 CEST; 43s ago
Docs: man:httpd.service(8)
Main PID: 7187 (httpd)
Status: "Total requests: 0; Idle/Busy workers 100/0;Requests/sec: 0; Bytes served/sec: 0 B/sec"
Tasks: 177 (limit: 48800)
Memory: 40.5M
CPU: 128ms
CGroup: /system.slice/httpd.service
├─7187 /usr/sbin/httpd -DFOREGROUND
├─7188 /usr/sbin/httpd -DFOREGROUND
├─7189 /usr/sbin/httpd -DFOREGROUND
├─7190 /usr/sbin/httpd -DFOREGROUND
└─7191 /usr/sbin/httpd -DFOREGROUND
Sep 26 15:01:28 redhat9.ittraining.loc systemd[1]: Starting The Apache HTTP Server...
Sep 26 15:01:28 redhat9.ittraining.loc httpd[7187]: Server configured, listening on: port 80
Sep 26 15:01:28 redhat9.ittraining.loc systemd[1]: Started The Apache HTTP Server.
Pour arrêter une Unité de service, utilisez la commande suivante :
[root@redhat9 ~]# systemctl stop httpd.service
[root@redhat9 ~]# systemctl status httpd.service
○ httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; preset: disabled)
Active: inactive (dead) since Thu 2024-09-26 15:02:55 CEST; 2s ago
Duration: 1min 26.084s
Docs: man:httpd.service(8)
Process: 7187 ExecStart=/usr/sbin/httpd $OPTIONS -DFOREGROUND (code=exited, status=0/SUCCESS)
Main PID: 7187 (code=exited, status=0/SUCCESS)
Status: "Total requests: 0; Idle/Busy workers 100/0;Requests/sec: 0; Bytes served/sec: 0 B/sec"
CPU: 178ms
Sep 26 15:01:28 redhat9.ittraining.loc systemd[1]: Starting The Apache HTTP Server...
Sep 26 15:01:28 redhat9.ittraining.loc httpd[7187]: Server configured, listening on: port 80
Sep 26 15:01:28 redhat9.ittraining.loc systemd[1]: Started The Apache HTTP Server.
Sep 26 15:02:54 redhat9.ittraining.loc systemd[1]: Stopping The Apache HTTP Server...
Sep 26 15:02:55 redhat9.ittraining.loc systemd[1]: httpd.service: Deactivated successfully.
Sep 26 15:02:55 redhat9.ittraining.loc systemd[1]: Stopped The Apache HTTP Server.
Pour désactiver un service au prochain démarrage du système, utilisez l'option disable :
[root@redhat9 ~]# systemctl disable httpd.service
Removed "/etc/systemd/system/multi-user.target.wants/httpd.service".
[root@redhat9 ~]# systemctl status httpd.service
○ httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled; preset: disabled)
Active: inactive (dead)
Docs: man:httpd.service(8)
Sep 26 15:01:28 redhat9.ittraining.loc systemd[1]: Starting The Apache HTTP Server...
Sep 26 15:01:28 redhat9.ittraining.loc httpd[7187]: Server configured, listening on: port 80
Sep 26 15:01:28 redhat9.ittraining.loc systemd[1]: Started The Apache HTTP Server.
Sep 26 15:02:54 redhat9.ittraining.loc systemd[1]: Stopping The Apache HTTP Server...
Sep 26 15:02:55 redhat9.ittraining.loc systemd[1]: httpd.service: Deactivated successfully.
Sep 26 15:02:55 redhat9.ittraining.loc systemd[1]: Stopped The Apache HTTP Server.
Systemd permet l'utilisation des gabarits (templates) des fichiers de configuration des Unités. De cette façon il est possible de faire coexister deux ou plusieurs instances du même service. Un gabarit est reconnaissable par le caractère @ qui est placé juste avant le point dans le nom du fichier :
[root@redhat9 ~]# cat /usr/lib/systemd/system/httpd@.service # This is a template for httpd instances. # See httpd@.service(8) for more information. [Unit] Description=The Apache HTTP Server After=network.target remote-fs.target nss-lookup.target Documentation=man:httpd@.service(8) [Service] Type=notify Environment=LANG=C Environment=HTTPD_INSTANCE=%i ExecStartPre=/bin/mkdir -m 710 -p /run/httpd/instance-%i ExecStartPre=/bin/chown root.apache /run/httpd/instance-%i ExecStartPre=/bin/mkdir -m 700 -p /var/lib/httpd/instance-%i ExecStartPre=/bin/chown apache.apache /var/lib/httpd/instance-%i ExecStart=/usr/sbin/httpd $OPTIONS -DFOREGROUND -f conf/%i.conf ExecReload=/usr/sbin/httpd $OPTIONS -k graceful -f conf/%i.conf # Send SIGWINCH for graceful stop KillSignal=SIGWINCH KillMode=mixed PrivateTmp=true OOMPolicy=continue [Install] WantedBy=multi-user.target
Une instance créée à partir de ce gabarit devrait avoir un nom sous la forme suivante :
httpd@<nom_instance>.service
Dans ce fichier on peut constater l'utilisation d'un identifier sous la forme de %i. Les identifiers sont de deux types - un dit échappé où les caractères non-ASCII alphanumérique sont remplacés par escapes de type langage C et l'autre non-échappé :
Créez maintenant deux copies du fichier /usr/lib/systemd/system/httpd@.service :
[root@redhat9 ~]# cp /usr/lib/systemd/system/httpd@.service /usr/lib/systemd/system/httpd@instance01.service [root@redhat9 ~]# cp /usr/lib/systemd/system/httpd@.service /usr/lib/systemd/system/httpd@instance02.service
Créez deux copies du fichier /etc/httpd/conf/httpd.conf :
[root@redhat9 ~]# cp /etc/httpd/conf/httpd.conf /etc/httpd/conf/instance01.conf [root@redhat9 ~]# cp /etc/httpd/conf/httpd.conf /etc/httpd/conf/instance02.conf
Editez la directive Listen du fichier /etc/httpd/conf/instance01.conf et ajoutez la directive PidFile :
[root@redhat9 ~]# vi /etc/httpd/conf/instance01.conf [root@redhat9 ~]# more /etc/httpd/conf/instance01.conf # # This is the main Apache HTTP server configuration file. It contains the # configuration directives that give the server its instructions. # See <URL:http://httpd.apache.org/docs/2.4/> for detailed information. # In particular, see # <URL:http://httpd.apache.org/docs/2.4/mod/directives.html> # for a discussion of each configuration directive. # # See the httpd.conf(5) man page for more information on this configuration, # and httpd.service(8) on using and configuring the httpd service. # # Do NOT simply read the instructions in here without understanding # what they do. They're here only as hints or reminders. If you are unsure # consult the online docs. You have been warned. # # Configuration and logfile names: If the filenames you specify for many # of the server's control files begin with "/" (or "drive:/" for Win32), the # server will use that explicit path. If the filenames do *not* begin # with "/", the value of ServerRoot is prepended -- so 'log/access_log' # with ServerRoot set to '/www' will be interpreted by the # server as '/www/log/access_log', where as '/log/access_log' will be # interpreted as '/log/access_log'. # # ServerRoot: The top of the directory tree under which the server's # configuration, error, and log files are kept. # # Do not add a slash at the end of the directory path. If you point # ServerRoot at a non-local disk, be sure to specify a local disk on the # Mutex directive, if file-based mutexes are used. If you wish to share the # same ServerRoot for multiple httpd daemons, you will need to change at # least PidFile. # ServerRoot "/etc/httpd" # # Listen: Allows you to bind Apache to specific IP addresses and/or # ports, instead of the default. See also the <VirtualHost> # directive. # # Change this to Listen on a specific IP address, but note that if # httpd.service is enabled to run at boot time, the address may not be # available when the service starts. See the httpd.service(8) man # page for more information. # #Listen 12.34.56.78:80 Listen 8008 PidFile /var/run/httpd/instance01.pid # # Dynamic Shared Object (DSO) Support # # To be able to use the functionality of a module which was built as a DSO you # have to place corresponding `LoadModule' lines at this location so the # directives contained in it are actually available _before_ they are used. --More--(19%) [q]
Editez la directive Listen du fichier /etc/httpd/conf/instance02.conf et ajoutez la directive PidFile :
[root@redhat9 ~]# vi /etc/httpd/conf/instance02.conf [root@redhat9 ~]# more /etc/httpd/conf/instance02.conf # # This is the main Apache HTTP server configuration file. It contains the # configuration directives that give the server its instructions. # See <URL:http://httpd.apache.org/docs/2.4/> for detailed information. # In particular, see # <URL:http://httpd.apache.org/docs/2.4/mod/directives.html> # for a discussion of each configuration directive. # # See the httpd.conf(5) man page for more information on this configuration, # and httpd.service(8) on using and configuring the httpd service. # # Do NOT simply read the instructions in here without understanding # what they do. They're here only as hints or reminders. If you are unsure # consult the online docs. You have been warned. # # Configuration and logfile names: If the filenames you specify for many # of the server's control files begin with "/" (or "drive:/" for Win32), the # server will use that explicit path. If the filenames do *not* begin # with "/", the value of ServerRoot is prepended -- so 'log/access_log' # with ServerRoot set to '/www' will be interpreted by the # server as '/www/log/access_log', where as '/log/access_log' will be # interpreted as '/log/access_log'. # # ServerRoot: The top of the directory tree under which the server's # configuration, error, and log files are kept. # # Do not add a slash at the end of the directory path. If you point # ServerRoot at a non-local disk, be sure to specify a local disk on the # Mutex directive, if file-based mutexes are used. If you wish to share the # same ServerRoot for multiple httpd daemons, you will need to change at # least PidFile. # ServerRoot "/etc/httpd" # # Listen: Allows you to bind Apache to specific IP addresses and/or # ports, instead of the default. See also the <VirtualHost> # directive. # # Change this to Listen on a specific IP address, but note that if # httpd.service is enabled to run at boot time, the address may not be # available when the service starts. See the httpd.service(8) man # page for more information. # #Listen 12.34.56.78:80 Listen 8009 PidFile /var/run/httpd/instance02.pid # # Dynamic Shared Object (DSO) Support # # To be able to use the functionality of a module which was built as a DSO you # have to place corresponding `LoadModule' lines at this location so the # directives contained in it are actually available _before_ they are used. --More--(19%) [q]
Démarrez les deux services :
[root@redhat9 ~]# systemctl start httpd@instance01.service
[root@redhat9 ~]# systemctl status httpd@instance01.service
● httpd@instance01.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd@instance01.service; disabled; preset: disabled)
Active: active (running) since Thu 2024-09-26 15:14:25 CEST; 9s ago
Docs: man:httpd@.service(8)
Process: 7424 ExecStartPre=/bin/mkdir -m 710 -p /run/httpd/instance-instance01 (code=exited, status=0/SUCCESS)
Process: 7425 ExecStartPre=/bin/chown root.apache /run/httpd/instance-instance01 (code=exited, status=0/SUCCESS)
Process: 7426 ExecStartPre=/bin/mkdir -m 700 -p /var/lib/httpd/instance-instance01 (code=exited, status=0/SUCCESS)
Process: 7427 ExecStartPre=/bin/chown apache.apache /var/lib/httpd/instance-instance01 (code=exited, status=0/SUCCESS)
Main PID: 7429 (httpd)
Status: "Total requests: 0; Idle/Busy workers 100/0;Requests/sec: 0; Bytes served/sec: 0 B/sec"
Tasks: 177 (limit: 48800)
Memory: 42.1M
CPU: 122ms
CGroup: /system.slice/system-httpd.slice/httpd@instance01.service
├─7429 /usr/sbin/httpd -DFOREGROUND -f conf/instance01.conf
├─7430 /usr/sbin/httpd -DFOREGROUND -f conf/instance01.conf
├─7431 /usr/sbin/httpd -DFOREGROUND -f conf/instance01.conf
├─7432 /usr/sbin/httpd -DFOREGROUND -f conf/instance01.conf
└─7433 /usr/sbin/httpd -DFOREGROUND -f conf/instance01.conf
Sep 26 15:14:24 redhat9.ittraining.loc systemd[1]: Starting The Apache HTTP Server...
Sep 26 15:14:25 redhat9.ittraining.loc httpd[7429]: Server configured, listening on: port 8008
Sep 26 15:14:25 redhat9.ittraining.loc systemd[1]: Started The Apache HTTP Server.
[root@redhat9 ~]# systemctl start httpd@instance02.service
[root@redhat9 ~]# systemctl status httpd@instance02.service
● httpd@instance02.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd@instance02.service; disabled; preset: disabled)
Active: active (running) since Thu 2024-09-26 15:14:43 CEST; 7s ago
Docs: man:httpd@.service(8)
Process: 7614 ExecStartPre=/bin/mkdir -m 710 -p /run/httpd/instance-instance02 (code=exited, status=0/SUCCESS)
Process: 7615 ExecStartPre=/bin/chown root.apache /run/httpd/instance-instance02 (code=exited, status=0/SUCCESS)
Process: 7616 ExecStartPre=/bin/mkdir -m 700 -p /var/lib/httpd/instance-instance02 (code=exited, status=0/SUCCESS)
Process: 7617 ExecStartPre=/bin/chown apache.apache /var/lib/httpd/instance-instance02 (code=exited, status=0/SUCCESS)
Main PID: 7618 (httpd)
Status: "Started, listening on: port 8009"
Tasks: 177 (limit: 48800)
Memory: 42.1M
CPU: 113ms
CGroup: /system.slice/system-httpd.slice/httpd@instance02.service
├─7618 /usr/sbin/httpd -DFOREGROUND -f conf/instance02.conf
├─7619 /usr/sbin/httpd -DFOREGROUND -f conf/instance02.conf
├─7620 /usr/sbin/httpd -DFOREGROUND -f conf/instance02.conf
├─7621 /usr/sbin/httpd -DFOREGROUND -f conf/instance02.conf
└─7622 /usr/sbin/httpd -DFOREGROUND -f conf/instance02.conf
Sep 26 15:14:43 redhat9.ittraining.loc systemd[1]: Starting The Apache HTTP Server...
Sep 26 15:14:43 redhat9.ittraining.loc httpd[7618]: Server configured, listening on: port 8009
Sep 26 15:14:43 redhat9.ittraining.loc systemd[1]: Started The Apache HTTP Server.
Il est possible d'interdire la modification en utilisant la commande systemctl mask:
[root@redhat9 ~]# systemctl status httpd.service
○ httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled; preset: disabled)
Active: inactive (dead)
Docs: man:httpd.service(8)
Sep 26 15:01:28 redhat9.ittraining.loc systemd[1]: Starting The Apache HTTP Server...
Sep 26 15:01:28 redhat9.ittraining.loc httpd[7187]: Server configured, listening on: port 80
Sep 26 15:01:28 redhat9.ittraining.loc systemd[1]: Started The Apache HTTP Server.
Sep 26 15:02:54 redhat9.ittraining.loc systemd[1]: Stopping The Apache HTTP Server...
Sep 26 15:02:55 redhat9.ittraining.loc systemd[1]: httpd.service: Deactivated successfully.
Sep 26 15:02:55 redhat9.ittraining.loc systemd[1]: Stopped The Apache HTTP Server.
[root@redhat9 ~]# systemctl mask httpd.service
Created symlink /etc/systemd/system/httpd.service → /dev/null.
[root@redhat9 ~]# systemctl enable httpd.service
Failed to enable unit: Unit file /etc/systemd/system/httpd.service is masked.
[root@redhat9 ~]# systemctl start httpd.service
Failed to start httpd.service: Unit httpd.service is masked.
Pour autoriser de nouveau les modifications, il convient d'utiliser la commande systemctl unmask :
[root@redhat9 ~]# systemctl unmask httpd.service
Removed "/etc/systemd/system/httpd.service".
[root@redhat9 ~]# systemctl enable httpd.service
Created symlink /etc/systemd/system/multi-user.target.wants/httpd.service → /usr/lib/systemd/system/httpd.service.
[root@redhat9 ~]# systemctl start httpd.service
[root@redhat9 ~]# systemctl status httpd.service
● httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; preset: disabled)
Active: active (running) since Thu 2024-09-26 15:17:38 CEST; 18s ago
Docs: man:httpd.service(8)
Main PID: 7896 (httpd)
Status: "Total requests: 0; Idle/Busy workers 100/0;Requests/sec: 0; Bytes served/sec: 0 B/sec"
Tasks: 177 (limit: 48800)
Memory: 40.1M
CPU: 99ms
CGroup: /system.slice/httpd.service
├─7896 /usr/sbin/httpd -DFOREGROUND
├─7897 /usr/sbin/httpd -DFOREGROUND
├─7898 /usr/sbin/httpd -DFOREGROUND
├─7899 /usr/sbin/httpd -DFOREGROUND
└─7900 /usr/sbin/httpd -DFOREGROUND
Sep 26 15:17:38 redhat9.ittraining.loc systemd[1]: Starting The Apache HTTP Server...
Sep 26 15:17:38 redhat9.ittraining.loc httpd[7896]: Server configured, listening on: port 80
Sep 26 15:17:38 redhat9.ittraining.loc systemd[1]: Started The Apache HTTP Server.
Copyright © 2024 Hugh Norris.