[SOLVED] Nagios not receiving SNMP data

tutigan · 05-18-2010, 01:14 AM

Hi all,

I have recently set up nagios on a ubuntu server (9.10), and set it up to monitor all the servers, switches etc, following the quickstart guide provided on the nagios website.
My problem is this:
I have setup the nagios-plugins, and tried to set it up to monitor the network switches via SNMP but receive the following error within the nagios web interface:
SNMP problem - No data received from host

I tried it from the command line, and got the exact same error.
Is there some further configuration I need to do to be able to get this data?
I've used up all my google-fu, and read over everyone else's problems on every forum I could find, but to no avail.

Any help will be greatly appreciated!

EricTRA · 05-18-2010, 01:29 AM

Hello and Welcome to LinuxQuestions,

Just like the error states, no data received from host. Have you checked that the devices you are querying support SNMP and that it's activated? Also check which version of SNMP is supported by your devices, and if a community string and/or user/password combination is set on the devices.

Kind regards,

Eric

tutigan · 05-18-2010, 01:51 AM

Quote:

Originally Posted by EricTRA

Have you checked that the devices you are querying support SNMP and that it's activated? Also check which version of SNMP is supported by your devices, and if a community string and/or user/password combination is set on the devices.

I have indeed, it is activated. I've tried changing the community string (in the switch and the switch.cfg), and changing/removing the password.
I know for a fact that it works, as it was being monitored by a nagios server previously, which was re-built without baking up the .conf, and the tech who set it up left, so no-one knows how he did it...

EricTRA · 05-18-2010, 02:40 AM

Hi,

That's bad practice of course, not having a backup file of a working configuration. Do you have any firewall blocking the SNMP ports?

Kind regards,

Eric

centosboy · 05-18-2010, 04:55 AM

Quote:

Originally Posted by tutigan

I have indeed, it is activated. I've tried changing the community string (in the switch and the switch.cfg), and changing/removing the password.
I know for a fact that it works, as it was being monitored by a nagios server previously, which was re-built without baking up the .conf, and the tech who set it up left, so no-one knows how he did it...

can we start with the basics..?
from the nagios machine, can you run an snmpwalk against the device(s) you want to monitor pls...?
I say start off with

Code:

snmpwalk -Os -c <communitystring> -v 1 <ipaddress>

If this doesnt give any output then there are issues.

A quick look at the snmp configuration on the target host should tell you what.

Most likely only certain machines are allowed to query the snmp target or the community string is incorrect...or like erictra says, the snmp version might not match..

tutigan · 05-19-2010, 01:26 AM

A big thanks to centosboy! When I tried it again from the command line, I realised I was forgetting the "c" next to 2 in the version...
Thanks for all your help guys, I truly appreciate it!

EricTRA · 05-19-2010, 02:26 AM

Hi,

That's great news indeed. Enjoy Linux.

Kind regards,

Eric