systemd - system and service manager
systemd is a system and service 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. It can work as a drop-in replacement for sysvinit.
To install systemd run:
# apt-get update # apt-get install systemd
The kernels in Debian wheezy are fine for systemd, but if you run a self-compiled kernel, make sure you have 2.6.39 or newer and enable the following options:
- CONFIG_IPV6=[y|m], optional, but highly recommended
CONFIG_FANOTIFY=y, optional, required for systemd readahead. available in Linux kernel >= 2.6.37.
For an up-to-date list, see section "REQUIREMENTS" in the upstream README file.
Known Issues and Workarounds
Issue #1: sysvinit vs. systemd-sysv
sysvinit is the current default init-system in Debian and is flagged as an "Essential" package. This means the package management tools will refuse to remove or replace the package unless forced. Also on dist-upgrades essential packages are preferred and will be re-installed. For more Details see chapters "3.8 Essential packages" and "5.6.9 Essential"
# $EDITOR /etc/default/grub GRUB_CMDLINE_LINUX_DEFAULT="quiet init=/lib/systemd/systemd" <--- Change this line # update-grub
Workaround #2: Install systemd-sysv and put package "on hold".
The problem with "Essential flag" needs some discussion with the sysvinit maintainer.
Sometimes it is necessary to investigate why systemd hangs on startup or on reboot/shutdown.
Solution #0: Remove "quiet" from Kernel command line (so called "cmdline" or "grub line")
Solution #1: Increase verbosity via cmdline: Add "systemd.log_target=kmsg systemd.log_level=debug"
Of course you can have a "temporary" persistent solution:
[ /etc/default/grub ] GRUB_CMDLINE_LINUX="systemd.log_target=kmsg systemd.log_level=debug" <--- Add here (by uncommenting you can easily switch to debug) # update-grub
In addition enhance cmdline with "systemd.sysv_console=1" (0: disabled, 1: enabled).
Solution #2: Increase verbosity via /etc/systemd/system.conf
LogLevel=debug <--- Uncomment this line and use "debug" (default: commented and "info") LogTarget=syslog-or-kmsg <--- Uncomment this line (default: commented) SysVConsole=yes <--- Uncomment this line (default: commented)
HINT: "man system" and "man systemd.conf" (Note: File is system.conf vs. man-page system*d*.conf)
HINT: How to check Kernel command line parameters/options?
# cat /proc/cmdline
NOTE on LogLevel (see systemd(1) and systemd.conf(5)):
"Set log level. As argument this accepts a numerical log level or the well-known syslog(3) symbolic names (lowercase): emerg, alert, crit, err, warning, notice, info, debug."
HINT: Keep a copy of /sbin/init from sysvinit package in case of rescue (so you can use init=/sbin/init.sysvinit in cmdline)!
# cp -av /sbin/init /sbin/init.sysvinit <--- Before installing systemd-sysv package
Bugs and Bug-Tracking-Systems
- For known bugs please see topic "Known Issues and Workarounds"
- Update more packages to ship systemd service files.
- Draft a packaging policy involving systemd (upgrade / install / removal).
- Provide integration for package maintainer tools
- invoke-rc.d/update-rc.d/service integration.
- Get Essential flag removed from sysvinit.
- Sort out what to do about pam_loginuid, and integration into the Debian PAM stack
- Decide what to do about group:lock (/var/lock).
- Make systemd-vconsole work. Investigate which of the console-* and kbd* packages are actually required and how to migrate the configuration.
Where to get help?
As systemd is a very young project (see ), we would appreciate to use the existing upstream infrastructure like mailing-list , IRC (#debian-systemd) and read Lennart's blog , etc. for following the development. Most people interested in systemd development (from diverse distributions) and Debian-specific packaging are around on IRC: #systemd (irc.freenode.net). Anyway, Debian-specific bugs should be sent to Debian-BTS (for example use report-bug tool).
Talk about current state of systemd in Debian and plans for Jessie at FOSDEM 2013 by Tollef Fog Heen and Michael Biebl <firstname.lastname@example.org>
Slides from the FOSDEM 2013 talk