A little bit about Systemd By: James Loyd

Some Basic Info Targets only Linux distributions It uses aggressive parallelization Replacement for Sysvinit Redhat project Udev’s source tree has been merged into systemd

What is Systemd “systemd is a system and session manager for Linux, compatible with SysV and LSB init scripts. systemd provides aggressive parallelization capabilities, uses socket and D-Bus activation for starting services, offers on-demand starting of daemons, keeps track of processes using Linux cgroups, supports snapshotting and restoring of the system state, maintains mount and automount points and implements an elaborate transactional dependency-based service control logic.” -from http://www.freedesktop.org/wiki/Software/systemd

Enabled by default in:

Available in (as an alternative)

Booting Differences

Socket Activation Not New Simultaneous start-up of services No need to configure dependencies explicitly If a service dies, the socket stays around Upgrade and restart a service on demand Replace a service at run- time

Logind Multi-seat managemet Session switch management SSH differs from a non-remote login

The Journal Centralized logger with meta-data Services must be started with Systemd to write to logs Child processes of services can also write to logs Users cannot write to logs they can only read them if given access

Interesting facts about Services Must identify with systemd Can be started on- demand Controlled by cgroups Startup services can be audited