Life is ...

systemctl

  • 起動サービスの状態確認

    • サービス

      # systemctl list-units --type=service

    • ソケットの状態出力

      # systemctl list-sockets
LISTEN                      UNIT                         ACTIVATES
/dev/log                    systemd-journald.socket      systemd-journald.service
/run/dbus/system_bus_socket dbus.socket                  dbus.service
/run/dmeventd-client        dm-event.socket              dm-event.service
/run/dmeventd-server        dm-event.socket              dm-event.service
/run/lvm/lvmetad.socket     lvm2-lvmetad.socket          lvm2-lvmetad.service
/run/lvm/lvmpolld.socket    lvm2-lvmpolld.socket         lvm2-lvmpolld.service
/run/systemd/initctl/fifo   systemd-initctl.socket       systemd-initctl.service
/run/systemd/journal/socket systemd-journald.socket      systemd-journald.service
/run/systemd/journal/stdout systemd-journald.socket      systemd-journald.service
/run/systemd/shutdownd      systemd-shutdownd.socket     systemd-shutdownd.service
/run/udev/control           systemd-udevd-control.socket systemd-udevd.service
/var/run/rpcbind.sock       rpcbind.socket               rpcbind.service
kobject-uevent 1            systemd-udevd-kernel.socket  systemd-udevd.service

13 sockets listed.
Pass --all to see loaded but inactive sockets, too.

  • 利用可能なサービス一覧

    # systemctl list-unit-files --type=service
UNIT FILE                                     STATE
arp-ethers.service                            disabled
auditd.service                                enabled
autovt@.service                               enabled
blk-availability.service                      disabled
brandbot.service                              static
(snip)

  • サービス状態確認

    # systemctl status sshd
● sshd.service - OpenSSH server daemon
   Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)
   Active: active (running) since 火 2018-06-12 15:15:07 JST; 1 day 23h ago
     Docs: man:sshd(8)
           man:sshd_config(5)
 Main PID: 1180 (sshd)
    Tasks: 1
   Memory: 5.0M
   CGroup: /system.slice/sshd.service
           └─1180 /usr/sbin/sshd -D

 6月 13 15:06:10 master sshd[12813]: Accepted publickey for root...c
 6月 13 16:00:06 master sshd[17472]: Accepted publickey for root...c
 6月 13 16:00:19 master sshd[18375]: Accepted publickey for root...c
 6月 14 08:14:56 master sshd[315]: Accepted publickey for root f...c
 6月 14 08:19:07 master sshd[346]: Accepted publickey for root f...c
 6月 14 08:29:53 master sshd[579]: Accepted publickey for root f...c
 6月 14 08:31:01 master sshd[609]: Accepted publickey for root f...c
 6月 14 08:48:17 master sshd[1610]: Accepted publickey for root ...c
 6月 14 09:00:15 master sshd[1806]: Accepted publickey for root ...c
 6月 14 14:52:47 master sshd[8391]: Accepted publickey for root ...c
Hint: Some lines were ellipsized, use -l to show in full.

    # systemctl is-enabled sshd

      - is-active
      - Check whether units are active
  - is-enabled
      - Check whether unit files are enabled
  - is-failed
      - Check whether units are failed

  • 個別サービスの有効化・無効化(mask, unmask)

    • 実行することで手動での起動も不可になる

    • 無効化

      # systemctl mask postfix.service
Created symlink from /etc/systemd/system/postfix.service to /dev/null.

      • 起動してみる

        # systemctl start postfix
Failed to start postfix.service: Unit is masked.

    • 有効化

      # systemctl unmask postfix
Removed symlink /etc/systemd/system/postfix.service.

  • サービスの依存関係の確認

    # systemctl list-dependencies

  • デフォルトの起動時のモード表示

    $ sudo systemctl get-default
multi-user.target

    • GUI モードに変更

      $ sudo systemctl set-default graphical.target
Removed /etc/systemd/system/default.target.
Created symlink /etc/systemd/system/default.target → /usr/lib/systemd/system/graphical.target.
$ sudo systemctl get-default
graphical.target

  • 起動しているタイマーの確認

    # systemctl list-timers
NEXT                         LEFT      LAST                         PASSED       UNIT                         ACTIVATES
木 2019-02-07 15:07:09 JST  689ms ago 木 2019-02-07 15:07:10 JST  10ms ago     myscript.timer               myscript.service
木 2019-02-07 15:07:09 JST  687ms ago 木 2019-02-07 15:07:10 JST  11ms ago     list-process.timer           list-process.service
金 2019-02-08 12:31:05 JST  21h left  木 2019-02-07 12:31:05 JST  2h 36min ago systemd-tmpfiles-clean.timer systemd-tmpfiles-clean.service

3 timers listed.
Pass --all to see loaded but inactive timers, too.