Script for monitoring graylog2 log file and restarting service

graylog2mon.sh

#!/bin/bash

#
# File:         logmon.sh
# Description: Restart graylog2 if the error message is found in the current log file. 
#
# History:
# Date          Author                  Comment
# 2012-02-01    Evan Ochs               initial version
#

#Log file to monitor
LOGFILE="/service/graylog2/log/main/current"

#Error message to watch for
ERRORMSG="WARN : org.graylog2.periodical.MessageCountWriterThread - Error in MessageCountWriterThread: null"

#Server hostname
HOSTSERVER=$(hostname)

#Tail the log file, following inode changes for log rotation
#Only check the last line, so we don't restart off of earlier errors
tail -n1 -F $LOGFILE |while read LINE
do
        #If the line contains the error, restart graylog2 and wait 30 seconds
        echo $LINE
        if [[ "$LINE" =~ "$ERRORMSG" ]]
        then
                echo "graylog2 is stopped. Restarting..."
                logger "graylog2 exception error found. Restarting graylog2."
                CURDATE=$(date)
#               sv restart graylog2
                sleep 30
                GRAYSTATUS=$(sv status graylog2)
                mail -s "graylog2 restart in $HOSTSERVER" [email protected] <<EOF
graylog2 on Scribe server $HOSTSERVER had an exception error:
$LINE
The service was restared by the monitoring script at $CURDATE.
The output of a "sv status gralog2" is:
$GRAYSTATUS

EOF

        fi
done