lxc-graceful

#!/bin/bash

########################################################################
#
# script written by Nelson Pascoal - used to gracefully shut down a 
# lxc container instance.
#
########################################################################

GREP=`which grep`
PS=`which ps`
AWK=`which awk`
KILL=`which kill`
WC=`which wc`
LXCINFO=`which lxc-info`

container=$1
conf="/etc/lxc/$container.conf"

if [ -e $conf ]
then
        running=`$LXCINFO -n $container | $GREP STOPPED | $WC -l`
        if [ $running -eq 0 ]
        then
                # discover pid for lxc-start process
                lxcid=`$PS -ef | $GREP $conf | $GREP -v $GREP | $AWK '{print $2}'`
                # use lxc-start process pid to discover correct init process
                initid=`$PS -ef | $GREP $lxcid | $GREP -v $GREP | $GREP init | $AWK '{print $2}'`

                # send shutdown signal to init process
                $KILL -SIGPWR $initid
                running=`$LXCINFO -n $container | $GREP STOPPED | $WC -l`

                echo -n "Waiting for container $container to stop."

                while [ $running -eq 0 ]
                do
                        sleep 1
                        echo -n "."
                        running=`$LXCINFO -n $container | $GREP STOPPED | $WC -l`
                done
		
		echo
                echo "Container $container stopped successfully"
                exit 0
        else
                echo "Container $container is currently is status STOPPED - container shutdown terminated"
                exit 2
        fi
else
        echo "Container config file $conf not found - unable to initiate container shutdown"
        exit 1
fi