Nagios io monitoring Error executing iostat command

Originally IO monitoring is good, yesterday because to install Postfix, uninstall the previous Sendmail,yum remove SendMail. Today to open Nagios, io monitoring is grayed out. The error is as follows: IOSTAT unknown-error executing IOSTAT command

Depressed the others are good. I'm going to do it manually under the machine.

cd/usr/local/nagios/libexec/

[Email protected] libexec]#./check_iostat

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

IOSTAT unknown-error Executing IOSTAT command

So I re-yum-y install Sysstat

At the time of execution:./check_iostat

OK the return value is normal. It is possible that some dependent packages were uninstalled when uninstalling the SendMail.