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Linux monitoring NTP



We have a group of Linux servers running SUSE Linux and we would like to monitor the NTP status. If we manually login to the servers we would do something like:

# ntpq -nc peers
which would return something like this:
     remote           refid      st t when poll reach   delay   offset  jitter
*     2 u   47  128  377    1.271    0.575   0.124

We can then see the offset and see if it is excessive or not.

We tried adding the SNTP sensor to one server as a test to see how it went, but it returns with a sensor timeout error.

Can you confirm that we should be able to monitor linux servers with the SNTP sensor. If not, can you confirm the best way in which to monitor NTP, I am guessing via some sort of custom SSH script sensor?


linux ntp prtg script sensor sntp ssh test

Created on May 16, 2014 3:39:58 AM

Last change on May 19, 2014 9:37:24 AM by  Torsten Lindner [Paessler Support]

2 Replies




thank you very much for your KB-Post. If the normal SNTP-Sensor does not work with the Suse-Linux Servers in this case, we would indeed recommend, using a self-written script, that is then used by the SSH Script Sensor. You could have the sensor then show the time offset in PRTG.

best regards.

Created on May 20, 2014 11:12:11 AM by  Torsten Lindner [Paessler Support]



You are getting the session time out error because NTP on linux is configured to ignore external query requests by default.

You can read the documentation http://support.ntp.org/bin/view/Support/AccessRestrictions#Section_6.5.1.

Edit the /etc/ntp.cfg file and add a line to allow the PRTG server to query the NTP server.

Replace the IP with your IP address IPv4: restrict

Hope this helps,

Created on Jul 24, 2015 8:08:57 PM

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.