====== RH124 systemd ======

===== Links =====

  * [[https://systemd.io/]]
  * [[https://www.freedesktop.org/software/systemd/man/latest/systemd.html]]
  * [[https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/10/html/using_systemd_unit_files_to_customize_and_optimize_your_system/index]]

===== systemd packages =====

<code>
$ rpm -qa "*systemd*"
systemd-libs-257-23.el10_2.1.alma.1.x86_64
rpm-plugin-systemd-inhibit-4.19.1.1-23.el10.alma.1.x86_64
systemd-pam-257-23.el10_2.1.alma.1.x86_64
systemd-257-23.el10_2.1.alma.1.x86_64
python3-systemd-235-11.el10.x86_64
systemd-udev-257-23.el10_2.1.alma.1.x86_64
$
</code>

===== Start, stop and status check =====

<code>
$ systemctl status sshd.service
$ sudo systemctl stop sshd.service
$ sudo systemctl start sshd.service
</code>

===== Enable and disable =====

<code>
$ systemctl disable sshd.service
$ systemctl enable sshd.service
</code>

===== /usr/lib/systemd/system/sshd.service =====

<code>
[Unit]
Description=OpenSSH server daemon
Documentation=man:sshd(8) man:sshd_config(5)
After=network.target sshd-keygen.target
Wants=sshd-keygen.target
# Migration for Fedora 38 change to remove group ownership for standard host keys
# See https://fedoraproject.org/wiki/Changes/SSHKeySignSuidBit
Wants=ssh-host-keys-migration.service

[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
</code>

===== More =====

<code>
$ systemctl --type help
$ systemctl list-units --type=target
$ systemctl get-default
</code>

How to add a "drop-in" ''override.conf'':

<code>
$ systemctl edit sshd.service
</code>