nagios IO监控 Error executing iostat command

本来io监控是好好的，昨天因为要装postfix，就卸载以前sendmail，yum remove sendmail。今天来打开nagios一开，io的监控成灰色的了。报错如下：IOSTAT UNKNOWN - Error executing iostat command

郁闷了别的都好好的。于我就去该机器下面手动执行一下。

cd /usr/local/nagios/libexec/

[root@13 libexec]# ./check_iostat 

Can't exec "iostat": No such file or directory at ./check_iostat line 68.

IOSTAT UNKNOWN - Error executing iostat command