SERVICE(8)SERVICE(8)NAMEservice - Manage an operating system service.
SYNOPSISservice [-c -r -n -p] (up|run|edit|update) <binary|self> [-args <args>]
[-dev <special>] [-devstyle <style>] [-period <ticks>] [-script <path>]
[-label <name>] [-config <path>] [-state <state>] [-maxtime <time>]
service down <label>
service refresh <label>
service restart <label>
service clone <label>
service shutdown
DESCRIPTION
The service utility instructs the reincarnation server (RS) to perform
an action for a given system service (an OS server or device driver).
The action may concern an existing system service (SHIFT+F6 to list
them all), or a new system service to be started (actions up and run).
ACTIONSservice up <binary>
Starts a new system service identified by the given <binary>, which
must be specified using an absolute path. When the service unexpectedly
exits (for example, as a result of a crash or a panic), RS will inter‐
cept the event and restart the service automatically. If the service
fails to restart, RS will automatically bring it down allowing for
graceful degradation of service. If a critical system service fails to
restart, RS will immediately resort to a system-wide panic. The up
action takes the following options:
-c RS normally relies on the binary on the disk to restart a system
service. The -c option instructs RS to keep an in-memory copy of
the binary and use the copy to restart the service upon termina‐
tion. This is necessary when the location on the disk may change
or if the service itself is required to read the binary from the
disk (e.g. the disk driver).
-r when saving an in-memory copy, instructs RS to reuse and share
the copy of an existing service with the same program name, if
available.
-n by default, RS performs blocking startup of the system service.
As a result, the up action does not terminate until the system
service completes initialization. The -n option changes the
default behavior by performing non-blocking startup and thus
terminating the up action immediately without waiting for the
service to complete initialization.
-p instructs RS to keep a replica of the system service in back‐
ground and use the replica to restart the service upon termina‐
tion. This is necessary when the service itself is required to
create a working service instance (e.g. PM).
-args <args>
specifies the command line arguments to use to run the program
given by <binary>. The default is to use no arguments.
-dev <special>
specifies the device file to associate to the system service
(used only for device drivers). The default is to associate no
device file to the service.
-devstyle <style>
specifies the device style to associate to the system service
(used only for device drivers). The list of supported device
styles is available in the header file <minix/dmap.h>. The
default is to associate no device style (STYLE_NDEV) to the ser‐
vice.
-period <ticks>
specifies the period to use for the system service. When a
period is specified, RS sends a ping request to the system ser‐
vice after every period. If the response does not arrive in
time, RS will kill the misbehaving service and restart a new
one. The period must be specified in ticks, but can be appended
with HZ to make it seconds. The default is to use no period for
the service.
-script <path>
specifies the recovery script to associate to the system ser‐
vice. When a recovery script is used, RS will not attempt to
restart the service upon termination. RS will instead invoke the
script and delegate the recovery process to it. The script may
perform several operations, including instructing RS to restart
the service (restart action) or bring it down (down action).
The default is to associate no recovery script to the service.
-label <name>
specifies the label to use for the system service. The label is
used to univoquely identify the system service. The default is
to use the program name as the label.
-config <path>
specifies the absolute path of the system configuration file
with the settings of the system service. See system.conf(5) for
the syntax to use in the system configuration file. The default
is to use the global system configuration file /etc/system.conf.
service run <binary>
Runs a new system service identified by the given <binary>, which must
be specified using an absolute path. Similar to service up <binary>,
but instructs RS not to restart the service upon termination. This
action is currently a shorthand for service up <binary> -script
/etc/rs.single, which uses a recovery script that simply brings down
the service upon termination. This action should be only used for
short-lived programs that need system service privileges and do not
require crash recovery support.
service edit <binary> [-label <name>]
Edits settings of an existing system service identified by the given
label <name>. This action can be used to dynamically update the proper‐
ties of any system service, including those contained in the boot image
(e.g. VM). There are a few exceptions to the properties that can be
actually overridden dynamically. For example, the device file and the
device style associated to the service will no be updated. This action
takes the same options supported by the up action.
service update <binary|self>
Live updates an existing system service with a new version identified
by the given <binary>, which must be specified using an absolute path.
The existing service will be identified from the label given (if
explicitly specified), or from the program name. If <self> is specified
as an argument instead, RS will perform a self update of the system
service (i.e. an update of the service with its own replica). This is
intended for testing purposes. In this case, a label <name> must be
explicitly specified. Live update support is still in an early stage of
development and is subject to change in future revisions. This action
takes all the options supported by the up action and the following
additional options:
-state <state>
specifies the state of the service required by the update. The
default is a state in which the service is blocked not process‐
ing any work.
-maxtime <time>
specifies the maximum amount time for the service to prepare for
the update. The default is 0 (unlimited).
service down <label>
Stops an existing system service identified by the given <label>. RS
will bring down the service without attempting to restart it. Critical
system services cannot be shut down.
service refresh <label>
Refreshes an existing system service identified by the given <label>.
RS will kill the service and attempt to restart it.
service restart <label>
Restarts an existing terminated system service identified by the given
<label>. This action can only be used from a recovery script.
service clone <label>
Clones an existing system service to create a replica RS will use to
restart the service upon termination.
service shutdown
Tells RS the system is about to shutdown and no system service should
be restarted upon termination.
EXAMPLESservice up /sbin/is -period 5HZ
# Start the IS server and check its status every 5
seconds.
service up /usr/sbin/dp8390 -args DPETH0=pci
# Start the DP8390 ethernet driver, passing one
argument.
service down lance # Stop the system service with label lance.
SEE ALSOsystem.conf(5), boot(8), monitor(8).
AUTHOR
Cristiano Giuffrida <giuffrida@cs.vu.nl>
SERVICE(8)
