X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=man%2Fsystemd.xml;h=e74d71b126f096a2fd78c404f8e271841ec97da1;hb=246756ca928adaee98edd0e67712e81d8f3255a6;hp=007705e4943ebaa296505c8e2195d2834be4747c;hpb=99ffae46d38f05b6c8bc09fe29e50a507ae8b79b;p=elogind.git diff --git a/man/systemd.xml b/man/systemd.xml index 007705e49..e74d71b12 100644 --- a/man/systemd.xml +++ b/man/systemd.xml @@ -73,6 +73,13 @@ are mostly equivalent when invoked from normal login sessions. See telinit8 for more information. + + When run as system instance, systemd interprets + the configuration file + system.conf, otherwise + session.conf. See + systemd.conf5 + for more information. @@ -88,28 +95,6 @@ Prints a short help text and exits. - - - - Set default unit to - activate on startup. If not specified - defaults to - default.target. - - - - - Tell systemd to run in - a particular mode. Argument is one of - , - . Normally it - should not be necessary to pass this - option, as systemd automatically - detects the mode it is started - in. This call is hence of little use - except for - debugging. - @@ -127,17 +112,12 @@ configuration items understood in unit definition files. - - - - Ask for confirmation when spawning processes. - Extract D-Bus interface introspection data. This is - mostly useful at build at install time + mostly useful at install time to generate data suitable for the D-Bus interfaces repository. Optionally the interface @@ -146,6 +126,61 @@ introspection data for all interfaces is dumped. + + + + Set default unit to + activate on startup. If not specified + defaults to + default.target. + + + + + + Tell systemd to run a + system instance (resp. session + instance), even if the process ID is + not 1 (resp. is 1), i.e. system is not + (resp. is) run as init process. + Normally it should not be necessary to + pass these options, as systemd + automatically detects the mode it is + started in. These options are hence of + little use except for + debugging. + + + + + Dump core on crash. This switch has no effect when run as session instance. + + + + + Run shell on crash. This switch has no effect when run as session instance. + + + + + Ask for confirmation when spawning processes. This switch has no effect when run as session instance. + + + + + Show terse service status information while booting. This switch has no effect when run as session instance. + + + + + Set log + target. Argument must be one of + , + , + , + , + . + @@ -162,17 +197,6 @@ , . - - - - Set log - target. Argument must be one of - , - , - , - , - . - @@ -210,7 +234,7 @@ configuration or dynamically from system state. Units may be active (meaning started, bound, plugged in, ... depending on the unit type), or inactive (meaning - stopped, unbound, unplugged, ...), as well is in the + stopped, unbound, unplugged, ...), as well as in the process of being activated or deactivated, i.e. between the two states. The following unit types are available: @@ -256,7 +280,7 @@ systemd units, which later may be restored by activating the saved snapshot unit. For more information see - systemd.automount5. + systemd.snapshot5. Timer units are useful for triggering activation of other units based on @@ -269,7 +293,7 @@ systemd. They are described in systemd.swap5. Path units may be used - activate other services when file system + to activate other services when file system objects change or are modified. See systemd.path5. @@ -281,7 +305,7 @@ systemd.special7. On boot systemd activates the target unit - default.target whose job it is to + default.target whose job is to activate on-boot services and other on-boot units by pulling them in via dependencies. Usually the unit name is just an alias (symlink) for either @@ -296,10 +320,68 @@ systemd.special7 for details about these target units. + Processes systemd spawns are placed in + individual Linux control groups named after the unit + which they belong to in the private systemd + hierarchy. (see cgroups.txt + for more information about control groups, or short + "cgroups"). systemd uses this to effectively keep + track of processes. Control group information is + maintained in the kernel, and is accessible via the + file system hierarchy (beneath + /cgroup/systemd/), or in tools + such as + ps1 + (ps xawf -eo pid,user,cgroup,args + is particularly useful to list all processes and the + systemd units they belong to.). + + systemd is compatible with the SysV init system + to a large degree: SysV init scripts are supported and + simply read as an alternative (though limited) + configuration file format. The SysV + /dev/initctl interface is + provided, and compatibility implementations of the + various SysV client tools are available. In addition to + that, various established Unix functionality such as + /etc/fstab or the + utmp database are + supported. + + systemd has a minimal transaction system: if a + unit is requested to start up or shut down it will add + it and all its dependencies to a temporary + transaction. Then, it will verify if the transaction + is consistent (i.e. whether the ordering of all units + is cycle-free). If it is not, systemd will try to fix + it up, and removes non-essential jobs from the + transaction that might remove the loop. Also, systemd + tries to suppress non-essential jobs in the + transaction that would stop a running service. Finally + it is checked whether the jobs of the transaction + contradict jobs that have already been queued, and + optionally the transaction is aborted then. If all + worked out and the transaction is consistent and + minimized in its impact it is merged with all already + outstanding jobs and added to the run + queue. Effectively this means that before executing a + requested operation, systemd will verify that it makes + sense, fixing it if possible, and only failing if it + really cannot work. + + Systemd contains native implementations of + various tasks that need to be executed as part of the + boot process. For example, it sets the host name or + configures the loopback network device. It also sets + up and mounts various API file systems, such as + /sys or + /proc. + For more information about the concepts and ideas behind systemd please refer to the Original - Announcement Document. + Design Document. @@ -386,7 +468,7 @@ when figuring out whether a service shall be enabled. Note that a service unit with a native unit configuration - file can be started by activating it + file cannot be started by activating it in the SysV runlevel link farm. @@ -656,6 +738,87 @@ + + Kernel Command Line + + When run as system instance systemd parses a few kernel command line arguments: + + + + systemd.unit= + + Overrides the unit to + activate on boot. Defaults to + default.target. This + may be used to temporarily boot into a + different boot unit, for example + rescue.target or + emergency.service. See + systemd.special7 + for details about these + units. + + + + systemd.log_target= + systemd.log_level= + systemd.log_color= + systemd.log_location= + + Controls log output, + with the same effect as the + $SYSTEMD_LOG_TARGET, $SYSTEMD_LOG_LEVEL, $SYSTEMD_LOG_COLOR, $SYSTEMD_LOG_LOCATION + environment variables described above. + + + + systemd.dump_core= + + Takes a boolean + argument. If + systemd dumps core when it + crashes. Otherwise no core dump is + created. Defaults to + . + + + + systemd.crash_shell= + + Takes a boolean + argument. If + systemd spawns a shell when it + crashes. Otherwise no core dump is + created. Defaults to + , for security + reasons, as the shell is not protected + by any password + authentication. + + + + systemd.crash_chvt= + + Takes an integer + argument. If positive systemd + activates the specified virtual + terminal when it crashes. Defaults to + -1. + + + + systemd.show_status= + + Takes a boolean + argument. If + shows terse service status updates on + the console during bootup. Defaults to + . + + + + + Sockets and FIFOs