systemd is a new init system and system manager which was implemented/adapted into all the major Linux distributions over the traditional SysV init systems. systemd is compatible with SysV and LSB init scripts. It can work as a drop-in replacement for sysvinit system. systemd is the first process get started by kernel and holding PID 1. It’s a parant process for everything and Fedora 15 is the first distribution which was adapted systemd instead of upstart. systemctl is command line utility and primary tool to manage the systemd daemons/services such as (start, restart, stop, enable, disable, reload & status). systemd uses .service files Instead of bash scripts (SysVinit uses). systemd sorts all daemons into their own Linux cgroups and you can see the system hierarchy by exploring /cgroup/systemd file.
The team proudly announced the release of systemd 230 on
May 21, 2016 with lot of new features and improvement.
Download & Install on systemd 230
Changes on systemd 230
- DNSSEC is now turned on by default in systemd-resolved (in “allow-downgrade” mode), it might create incompatibilities with a few DNS servers and networks. Whenever it’s detect such incompatible setups then it will automatically downgrade to non-DNSSEC mode.
- systemd-resolve conveniently resolves DANE records with the –tlsa option and OPENPGPKEY records with the –openpgp option. It also supports dumping raw DNS record data via the new –raw= switch.
- systemd-logind will now by default terminate user processes that are part of the user session scope unit (session-XX.scope) when the user logs out.
- systemd-logind gained new configuration settings SessionsMax= and InhibitorsMax=, both with a default of 8192.
- systemd-logind will now reload configuration on SIGHUP.
- The unified cgroup hierarchy added in Linux Kernel 4.5 is now supported. Use systemd.unified_cgroup_hierarchy=1 on the kernel command line to enable.
- systemd-journald now uses separate threads to flush changes to disk when closing journal files, thus reducing impact of slow disk I/O on logging performance.
- systemd-ask-password now optionally skips printing of the password to stdout with –no-output which can be useful in scripts.
- The DeviceAllow= unit setting now supports specifiers (with “%”).
- For more details