Monitor system mem and load, if too high, restart some service.

mt-mon.sh

#! /bin/bash
#====================================================================
#	mt-mon.sh
#
#	Copyright (c) 2011, Fwolf <[email protected]>
#	All rights reserved.
#	Distributed under the GNU General Public License, version 3.0.
#
#	Monitor system mem and load, if too high, restart some service.
#
#	See: https://wangyan.org/blog/pid-auto-reboot-shell-html.html
#
#	V 0.01, since 2011-08-24, hash: .
#====================================================================


if [ $(id -u) != '0' ]; then
    echo 'Error: You must be root to run this script!'
    exit 1
fi


# Max allowed mem usage
MON_MAX_MEM=85
# Max allowed cpu usage
MON_MAX_CPU=3
# If max exceed, restart thest service
MON_SERVICE='httpd'


function GetStat {
	# Mem, total
	MEM_TOTAL=`free -k | head -n2 | tail -n1 | awk '{print $2}'`
	# Mem, used
	MEM_USED=`free -k | head -n2 | tail -n1 | awk '{print $3 - $6 - $7}'`
	#echo Used mem: ${MEM_USED}k

	# Cpu load
	CPU_LOAD=`uptime | awk '{print $(NF-2)}' | sed 's/,//'`
	#echo Cpu load: $CPU_LOAD
}


GetStat
#echo Mem: ${MEM_USED}k/${MEM_TOTAL}k, Cpu load: $CPU_LOAD

# Compare
MEM_LIMIT=`echo $MEM_TOTAL \* $MON_MAX_MEM / 100 | bc`
if [[ $MEM_USED > $MEM_LIMIT || $CPU_LOAD > $MON_MAX_CPU ]]; then
	echo $(date +'%Y-%m-%d %H:%M:%S') mem or cpu max usage reached,
	echo Mem: ${MEM_USED}k/${MEM_TOTAL}k, Cpu load: $CPU_LOAD
	echo Restart service: $MON_SERVICE

	for SERVICE in $MON_SERVICE; do
		/etc/init.d/$SERVICE restart
	done

	GetStat
	echo Mem: ${MEM_USED}k/${MEM_TOTAL}k, Cpu load: $CPU_LOAD
	echo
fi

运行的时候输出到日志即可
mt-mon.sh >> /var/log/mt-mon.log