Nagios Support Forum

Hi All.

Running a Nagios server with verious clients running the NRPE plugin. I have a script for checking mysql replication. If I run it direct from the main Nagios server /usr/lib/nagios/plugins/check_nrpe -H monitored.com -c check_mysql NRPE: Unable to read output

If you run the following command from the host /usr/local/nagios/libexec/check-mysql-slave.pl
OK - Waiting for master to send event, replicating host xx.xx.xx.xx:3306

This is what is in the client nrpe.cfg command[check_sql]=/usr/local/nagios/libexec/check-mysql-slave.pl

This in on the nagios server

define service{
use generic-service
host_name server102.xxxxxx.co.uk
service_description # SQL replication
#contact_groups ux-admins, noc-op
check_command check_nrpe!check_sql
}

I have a similar script running for a memory check which did not work until I installed apt-get install bc on the Ubuntu box, although I did not see any errors in the syslog. Just wondering if I need something installed along these lines for it to be seen.

This is the debug details

May 24 09:21:44 slave nrpe[25294]: INFO: SSL/TLS initialized. All network traffic will be encrypted.
May 24 09:21:44 slave nrpe[25294]: Handling the connection...
May 24 09:21:44 slave nrpe[25294]: Host is asking for command 'check_sql' to be run...
May 24 09:21:44 slave nrpe[25294]: Running command: /usr/local/nagios/libexec/check-mysql-slave.pl
May 24 09:21:44 slave nrpe[25294]: Command completed with return code 3 and output:
May 24 09:21:44 slave nrpe[25294]: Return Code: 3, Output: NRPE: Unable to read output


The file has the correct permissions and owner. Am a little confused where I may be going wrong here. Can anyone advise me

Just to verify - are you running:
or

Sorry for the delay. Did not know I had a reply. I have been tweaking and playing since.

If I run the file directly on the host machine
/usr/local/nagios/libexec/check-mysql-slave.pl

I get the correct responce
OK - Waiting for master to send event, replicating host xx.xx.xx.xx:3306

When I run this using the NRPE check
/usr/local/nagios/libexec/check_nrpe -H localhost -c check-mysql-replication

I get NRPE: Unable to read output

I have the users on the file set as nagios as I should and I have the file set with the correct permissions

What happens when you run on the client?
Do you get the NRPE version? For example:
Are you using xinetd?

Thanks for the reply

When I run /usr/local/nagios/libexec/check_nrpe -H localhost

It do get NRPE v2.12

I have another script running on there checking memory and this works with no issues at all.

Thanks

Opps sorry yes using xinetd

Do you get the correct response when running your script on the system locally as the nagios user?

Yes I get the correct responce

OK - Waiting for master to send event, replicating host xx.xx.xx.xx:3306

Thanks

Can you connect to your client from your nagios server?

Run the following commands in terminal on your nagios server and post the output:
or/and