Systemd

Photon OS manages services with systemd and systemctl, its command-line utility for inspecting and controlling the system. It does not use the deprecated commands of init.d.

Basic system administration commands on Photon OS differ from those on operating systems that use SysVinit. Since Photon OS uses systemd instead of SysVinit, you must use systemd commands to manage services.

For example, instead of running the /etc/init.d/ssh script to stop and start the OpenSSH server on a init.d-based Linux system, you control the service by running the following systemctl commands on Photon OS:

systemctl stop sshd
systemctl start sshd

• Enabling systemd Debug Shell During Boot
• Troubleshooting Services with systemctl
• Analyzing System Logs with journalctl
• Inspecting Services with systemd-analyze
• General systemd Troubleshooting

For an overview of systemd, see systemd System and Service Manager and the man page for systemd. The systemd man pages are listed at https://www.freedesktop.org/software/systemd/man/.