The program systemd is the process with process ID 1. It is responsible for initializing the system in
the required way. systemd is started directly by the kernel and resists signal 9, which normally
terminates processes. All other programs are either started directly by systemd or by one of its child
processes.
The system initialization system used in SLES 15 is systemd. It is a modern and powerful system and
service manager that replaces the traditional init system. It provides faster boot times, better
dependency
handling,
parallelization,
and
more
features
and
capabilities.
Reference:
https://documentation.suse.com/sles/15-SP3/html/SLES-all/cha-systemd-basics.html
