sv(8)
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 /etc/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.
sv actually looks only at the first character of these commands.
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, 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.
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 /etc/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
runsv(8), chpst(8), svlogd(8), runsvdir(8), runsvchdir(8), runit(8), runit-init(8) http://smarden.org/runit/
AUTHOR
Gerrit Pape <pape@smarden.org>
sv(8)
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