Linux磁盘空间监控告警

Linux系统中需要监控磁盘各分区的使用情况，避免由于各种突发情况，造成磁盘空间被消耗殆尽的情况，例如某个分区被Oracle的归档日志耗尽，导致后续的日志文件无法归档，这时ORACLE数据库就会出现错误。监控磁盘空间的使用情况，其实有许多工具，例如Nagios等，其实最简单的还是使用Shell脚本。下面就介绍一下如何通过Shell脚本和Crontab作业结合来实现对磁盘空间的监控、告警。

一般查看磁盘各分区的使用情况可以通过df命令来查看，网上有两种获取磁盘使用百分比的Shell脚本。

1：df -h | grep /dev | awk '{print $5}' | cut -f 1 -d "%"

2：df -h | grep /dev | awk '{print $5}' | sed 's/%//g'

但是这两个命令还是有些bug，例如如下截图所示：当显示内容过长，导致换行时。此时上面的Shell脚本就无法获取其值。

尤其是某些特殊情况下，完全无法准确获取相应数据

此时只需在参数上稍微做一下调整即可

1：df -P | grep /dev | awk '{print $5}' | cut -f 1 -d "%"

2：df -P | grep /dev | awk '{print $5}' | sed 's/%//g'

下面脚本是用来监控各分区使用情况，当超过阀值（默认为90%）时，发出告警邮件，通知管理员及时处理。

#*************************************************************************
#  FileName     :               disk_capatiy_alarm.sh
#*************************************************************************
#  Author       :               Kerry
#  CreateDate   :               --
#  Description  :               this script is mointoring the linux disk
#                               capacity, if disk used more than %,
#                               then it will send a alarm email
#*************************************************************************

#! /bin/bash

email_content="/home/oracle/scripts/output/disk_sendmail.pl"
email_logfile="/home/oracle/scripts/output/diskdetail.txt";

cat /dev/null > ${email_content};
cat /dev/null > ${email_logfile};

SendMail()
{

date_today=`date +%Y_%m_%d`
subject="The server xxxxxx\'s Disk Capacity Alarm"
content="Dear All,

   The server xxxx(xxx.xxx.xxx.xxx) disk capacity alarm ,please  take action for it. many thanks!

"

echo "#!/usr/bin/perl" >> ${email_content}
echo "use Mail::Sender;" >> ${email_content}
echo "\$sender = new Mail::Sender {smtp => 'xxx.xxx.xxx.xxx', from => 'xxx@xxx.com'}; ">> ${email_content}
echo "\$sender->MailFile({to => 'kerry@xxx.com',">> ${email_content}
echo "cc=>'xxxx@xxxx.com'," >> ${email_content}
echo "subject => '$subject',">> ${email_content}
echo "msg => '$content',">> ${email_content}
echo "file => '${email_logfile}'});">> ${email_content}

perl ${email_content}

}

for d in `df -P | grep /dev | awk '{print $5}' | sed 's/%//g'` 

 do

    if [ $d -gt  ]; then

           df -h >>$email_logfile;

           SendMail;

             exit ;

    fi

done