[SOLVED] NRPE: Unable to read output (With a twist)

w00dy101 · 04-02-2013, 08:23 AM

Hi Guys

I am experimenting with Opsview community edition, for a small network of about 20 or so servers.

So far so good, using NRPE and all is hunky dory, except for one service check...

NRPE: Unable to read output

I've checked permissions, ownership and all is otherwise well (Other NRPE dependent checks are running just fine on this very same host), have also ensured that its not a sudo/root problem as seems to be common when googling the subject.

Have checked running the script on the host itself, it returns a result as expected. Its just when running it from the monitoring server that this error occurs. (Manually and via Opsview)

So I wonder why this is happening, I cant really reboot the server without scheduling it either.

Any pointers?

Habitual · 04-02-2013, 10:51 AM

show us the exact command that generates "NRPE: Unable to read output" please.
It fails on checks to all 20 or so hosts?
NRPE version?
How was it installed?

slokie · 04-02-2013, 05:12 PM

latest versions seem to have issues with items other than shell or perl based scripts - if you're running a ruby script I've had it call it within perl and let perl manipulate the output

w00dy101 · 04-03-2013, 12:25 AM

Opsview Server:

Code:

fabz@megathron:~$ /usr/local/nagios/libexec/check_nrpe -H localhost
NRPE v2.12

Remote Host:

Code:

fabz@megathron:~$ /usr/local/nagios/libexec/check_nrpe -H 10.1.75.199
NRPE v2.14 (OpsviewAgent 4.3.2.224; osname=Linux; osvers=2.6.24-30-server; desc=Ubuntu 8.04.4 LTS)

Opsview Server running command on remote host:

Code:

fabz@megathron:~$ /usr/local/nagios/libexec/check_nrpe -H 10.1.75.199 -c check_ps.sh -a '-p LabelPrinter1Server'
NRPE: Unable to read output

Remote Host running command locally:

Code:

arctec@arctec-feol01:~$ /usr/local/nagios/libexec/check_ps.sh -p LabelPrinter1Server
OK - Process: LabelPrinter1Server, User: arctec, CPU: 0.4%, RAM: 1.7%, Start: Mar20, CPU Time: 5303 min | 'cpu'=0.4 'memory'=1.7 'cputime'=5303

Opsview agent was installed as on Opsview documentation site. And no, I have not yet put this particular check on any other hosts but this one.

So am I being silly or what? :P

Also, the script being used is just a shell script.
http://exchange.nagios.org/directory...s-2Esh/details

Thank you in advance!

w00dy101 · 04-03-2013, 04:14 AM

Shame on me!

I have discovered the problem, typo in the command definition in nrpe.cfg.

command[check_ps.sh]=/usr/local/nagios/linexec/check_ps.sh $ARG1$

Sorry to have wasted your time people, after correcting, all is well with the world

The error NRPE: Unable to read output doesn't really indicate much in this regard... anyhoo

Thanks again to all who looked at this anyway

Ciao