sv

Name

sv - control and manage services monitored by runsv(8)

Synopsis

sv [-v] [-w sec] command services /etc/init.d/service [-w sec] command

Description

The sv program reports the current status and controls the state of services monitored by the runsv(8) supervisor. services consists of one or more arguments, each argument naming a directory service used by runsv(8). If service doesn’t start with a dot or slash and doesn’t end with a slash, it is searched in the default services directory /service/, otherwise relative to the current directory.

command is one of up, down, status, once, pause, cont, hup, alarm, interrupt, 1, 2, term, kill, or exit, or start, stop, restart, shutdown, force-stop, force-reload, force-restart, force-shutdown.

The sv program can be sym-linked to /etc/init.d/ to provide an LSB init script interface. The service to be controlled then is specified by the base name of the ‘‘init script’’.

Commands

status
Report the current status of the service, and the appendant log service if available, to standard output.

up
If the service is not running, start it. If the service stops, restart it.

down
If the service is running, send it the TERM signal, and the CONT signal. If ./run exits, start ./finish if it exists. After it stops, do not restart service/

once
If the service is not running, start it. Do not restart it if it stops. pause cont hup alarm interrupt quit 1 2 term kill If the service is running, send it the STOP, CONT, HUP, ALRM, INT, QUIT, USR1, USR2, TERM, or KILL signal respectively.

exit
If the service is running, send it the TERM signal, and the CONT signal. Do not restart the service. If the service is down, and no log service exists, runsv(8) exits. If the service is down and a log service exists, runsv(8) closes the standard input of the log service and waits for it to terminate. If the log service is down, runsv(8) exits. This command is ignored if it is given to an appendant log service.

NOTE: sv only looks at the first character of these commands, so you can truncate accordingly.

Commands compatible to LSB init script actions

status
Same as status.

start
Same as up, but wait up to 7 seconds for the command to take effect. Then report the status or timeout. If the script ./check exists in the service directory, sv runs this script to check whether the service is up and available; it’s considered to be available if ./check exits with 0.

stop
Same as down, but wait up to 7 seconds for the service to become down. Then report the status or timeout.

reload
Same as hup, and additionally report the status afterwards.

restart
Send the commands term, cont, and up to the service, and wait up to 7 seconds for the service to restart. Then report the status or timeout. If the script ./check exists in the service directory, sv runs this script to check whether the service is up and available again; it’s considered to be available if ./check exits with 0.

shutdown
Same as exit, but wait up to 7 seconds for the runsv(8) process to terminate. Then report the status or timeout.

force-stop
Same as down, but wait up to 7 seconds for the service to become down. Then report the status, and on timeout send the service the kill command.

force-reload
Send the service the term and cont commands, and wait up to 7 seconds for the service to restart. Then report the status, and on timeout send the service the kill command.

force-restart
Send the service the term, cont and up commands, and wait up to 7 seconds for the service to restart. Then report the status, and on timeout send the service the kill command. If the script ./check exists in the service directory, sv runs this script to check whether the service is up and available again; it’s considered to be available if ./check exits with 0.

force-shutdown
Same as exit, but wait up to 7 seconds for the runsv(8) process to terminate. Then report the status, and on timeout send the service the kill command.

try-restart
if the service is running, send it the term and cont commands, and wait up to 7 seconds for the service to restart. Then report the status or timeout.

Additional Commands

check
Check for the service to be in the state that’s been requested. Wait up to 7 seconds for the service to reach the requested state, then report the status or timeout. If the requested state of the service is up (Distinction here... If the service is in the down state the check script won't be checked.), and the script ./check exists in the service directory, sv runs this script to check whether the service is up and running; it’s considered to be up if ./check exits with 0. If there is no check file in the service directory's config files, it is presumed that if the service is in an executing state at the time of the check call that the service is, "up".

Options

-v
If the command is up, down, term, once, cont, or exit, then wait up to 7 seconds for the command to take effect. Then report the status or timeout.

-w sec
Override the default timeout of 7 seconds with sec seconds. This option implies -v.

Environment

SVDIR

The environment variable $SVDIR overrides the default services directory /service/.

SVWAIT

The environment variable $SVWAIT overrides the default 7 seconds to wait for a command to take effect. It is overridden by the -w option.

Exit Codes

sv exits 0, if the command was successfully sent to all services, and, if it was told to wait, the command has taken effect to all services.

For each service that caused an error (e.g. the directory is not controlled by a runsv(8) process, or sv timed out while waiting), sv increases the exit code by one and exits non zero. The maximum is 99. sv exits 100 on error.

If sv is called with a base name other than sv: it exits 1 on timeout or trouble sending the command; if the command is status, it exits 3 if the service is down, and 4 if the status is unknown; it exits 2 on wrong usage, and 151 on error.

See Also

runit(8), runit-init(8),runsvdir(8), runsvchdir(8), runsv(8), chpst(8), utmpset(8), svlogd(8)

Authors

Gerrit Pape pape@smarden.org
Frank Earl linusti@gmail.com