Linux服务器硬件运行状态及故障邮件提醒的监控脚本分享

监控硬件运行状况

shell 监控cpu，memory，load average，记录到log，当负载压力时，发电邮通知管理员。
原理：
1.获取cpu，memory，load average的数值
2.判断数值是否超过自定义的范围，例如（CPU>90%，Memory<10%，load average>2）
3.如数值超过范围，发送电邮通知管理员。发送有时间间隔，每小时只会发送一次。
4.将数值写入log。
5.设置crontab 每30秒运行一次。

ServerMonitor.sh

#!/bin/bash 

# 系统监控,记录cpu、memory、load average,当超过规定数值时发电邮通知管理员 

# *** config start *** 

# 当前目录路径
ROOT=$(cd "$(dirname "$0")"; pwd) 

# 当前服务器名
HOST=$(hostname) 

# log 文件路径
CPU_LOG="${ROOT}/logs/cpu.log"
MEM_LOG="${ROOT}/logs/mem.log"
LOAD_LOG="${ROOT}/logs/load.log" 

# 通知电邮列表
NOTICE_EMAIL='admin@admin.com' 

# cpu,memory,load average 记录上一次发送通知电邮时间
CPU_REMARK='/tmp/servermonitor_cpu.remark'
MEM_REMARK='/tmp/servermonitor_mem.remark'
LOAD_REMARK='/tmp/servermonitor_loadaverage.remark' 

# 发通知电邮间隔时间
REMARK_EXPIRE=3600
NOW=$(date +%s) 

# *** config end *** 

# *** function start *** 

# 获取CPU占用
function GetCpu() {
  cpufree=$(vmstat 1 5 |sed -n '3,$p' |awk '{x = x + $15} END {print x/5}' |awk -F. '{print $1}')
  cpuused=$((100 - $cpufree))
  echo $cpuused 

  local remark
  remark=$(GetRemark ${CPU_REMARK}) 

  # 检查CPU占用是否超过90%
  if [ "$remark" = "" ] && [ "$cpuused" -gt 90 ]; then
    echo "Subject: ${HOST} CPU uses more than 90% $(date +%Y-%m-%d' '%H:%M:%S)" | sendmail ${NOTICE_EMAIL}
    echo "$(date +%s)" > "$CPU_REMARK"
  fi
} 

# 获取内存使用情况
function GetMem() {
  mem=$(free -m | sed -n '3,3p')
  used=$(echo $mem | awk -F ' ' '{print $3}')
  free=$(echo $mem | awk -F ' ' '{print $4}')
  total=$(($used + $free))
  limit=$(($total/10))
  echo "${total} ${used} ${free}" 

  local remark
  remark=$(GetRemark ${MEM_REMARK}) 

  # 检查内存占用是否超过90%
  if [ "$remark" = "" ] && [ "$limit" -gt "$free" ]; then
    echo "Subject: ${HOST} Memory uses more than 90% $(date +%Y-%m-%d' '%H:%M:%S)" | sendmail ${NOTICE_EMAIL}
    echo "$(date +%s)" > "$MEM_REMARK"
  fi
} 

# 获取load average
function GetLoad() {
  load=$(uptime | awk -F 'load average: ' '{print $2}')
  m1=$(echo $load | awk -F ', ' '{print $1}')
  m5=$(echo $load | awk -F ', ' '{print $2}')
  m15=$(echo $load | awk -F ', ' '{print $3}')
  echo "${m1} ${m5} ${m15}" 

  m1u=$(echo $m1 | awk -F '.' '{print $1}') 

  local remark
  remark=$(GetRemark ${LOAD_REMARK}) 

  # 检查是否负载是否有压力
  if [ "$remark" = "" ] && [ "$m1u" -gt "2" ]; then
    echo "Subject: ${HOST} Load Average more than 2 $(date +%Y-%m-%d' '%H:%M:%S)" | sendmail ${NOTICE_EMAIL}
    echo "$(date +%s)" > "$LOAD_REMARK"
  fi
} 

# 获取上一次发送电邮时间
function GetRemark() {
  local remark 

  if [ -f "$1" ] && [ -s "$1" ]; then
    remark=$(cat $1) 

    if [ $(( $NOW - $remark )) -gt "$REMARK_EXPIRE" ]; then
      rm -f $1
      remark=""
    fi
  else
    remark=""
  fi 

  echo $remark
} 

# *** function end *** 

cpuinfo=$(GetCpu)
meminfo=$(GetMem)
loadinfo=$(GetLoad) 

echo "cpu: ${cpuinfo}" >> "${CPU_LOG}"
echo "mem: ${meminfo}" >> "${MEM_LOG}"
echo "load: ${loadinfo}" >> "${LOAD_LOG}" 

exit 0

监控网站是否异常
shell 监控网站是否异常的脚本，如有异常自动发电邮通知管理员。
流程：
1.检查网站返回的http_code是否等于200，如不是200视为异常。
2.检查网站的访问时间，超过MAXLOADTIME（10秒）视为异常。
3.发送通知电邮后，在/tmp/monitor_load.remark记录发送时间，在一小时内不重复发送，如一小时后则清空/tmp/monitor_load.remark。

#!/bin/bash 

SITES=("http://web01.example.com" "http://web02.example.com") # 要监控的网站
NOTICE_EMAIL='me@example.com'                 # 管理员电邮
MAXLOADTIME=10                        # 访问超时时间设置
REMARKFILE='/tmp/monitor_load.remark'             # 记录时否发送过通知电邮，如发送过则一小时内不再发送
ISSEND=0                           # 是否有发送电邮
EXPIRE=3600                          # 每次发送电邮的间隔秒数
NOW=$(date +%s) 

if [ -f "$REMARKFILE" ] && [ -s "$REMARKFILE" ]; then
  REMARK=$(cat $REMARKFILE) 

  # 删除过期的电邮发送时间记录文件
  if [ $(( $NOW - $REMARK )) -gt "$EXPIRE" ]; then
    rm -f ${REMARKFILE}
    REMARK=""
  fi
else
  REMARK=""
fi 

# 循环判断每个site
for site in ${SITES[*]}; do 

  printf "start to load ${site}\n"
  site_load_time=$(curl -o /dev/null -s -w "time_connect: %{time_connect}\ntime_starttransfer: %{time_starttransfer}\ntime_total: %{time_total}" "${site}")
  site_access=$(curl -o /dev/null -s -w %{http_code} "${site}")
  time_total=${site_load_time##*:} 

  printf "$(date '+%Y-%m-%d %H:%M:%S')\n"
  printf "site load time\n${site_load_time}\n"
  printf "site access:${site_access}\n\n" 

  # not send
  if [ "$REMARK" = "" ]; then
    # check access
    if [ "$time_total" = "0.000" ] || [ "$site_access" != "200" ]; then
      echo "Subject: ${site} can access $(date +%Y-%m-%d' '%H:%M:%S)" | sendmail ${NOTICE_EMAIL}
      ISSEND=1
    else
      # check load time
      if [ "${time_total%%.*}" -ge ${MAXLOADTIME} ]; then
        echo "Subject: ${site} load time total:${time_total} $(date +%Y-%m-%d' '%H:%M:%S)" | sendmail ${NOTICE_EMAIL}
        ISSEND=1
      fi
    fi
  fi 

done 

# 发送电邮后记录发送时间
if [ "$ISSEND" = "1" ]; then
  echo "$(date +%s)" > $REMARKFILE
fi 

exit 0