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Filter certain syslog messages while still saving them



I have a Cisco Catalyst 2960 switch sending syslog messages to PRTG. I would like to stop getting alerts on interface UPDOWN events (i.e. if a computer is rebooted, powered off, unplugged, etc.).

The default configuration of the PRTG Syslog sensor is:

Include: severity[0-6]
Warn on: severity[4]
Alert on: severity[0-3]

Some of these UPDOWN messages come with severity 5 and some are severity 3. This means sometimes they cause sensor failures, and other times they don't. I'm not sure why Cisco sends them with 2 different priorities. Will need to do some research there.

I would like to exclude the UPDOWN messages from causing Alerts (in the cases where the severity is 3). How can I do this while still:

  1. Receiving an alert for all other severity 0-3 messages
  2. Still logging/saving the UPDOWN messages? (retaining these messages can be highly valuable for retroactive troubleshooting).

Thanks in advance for your help with this.

- Doug

exclude log syslog

Created on Oct 20, 2016 4:44:08 AM

Last change on Oct 24, 2016 5:37:37 AM by  Luciano Lingnau [Paessler]

5 Replies



How exactly does the UPDOWN message look? We could simply add it to the error filter like this: (severity[0-3] AND NOT message[UPDOWN])

Created on Oct 21, 2016 12:29:39 PM by  Stephan Linke [Paessler Support]




Thanks for your recommendation. Your solution of using the "AND NOT" logic worked perfectly. I am using your syntax verbatim.

Created on Oct 21, 2016 9:24:40 PM



Glad it worked out :)

Created on Oct 24, 2016 5:43:51 AM by  Stephan Linke [Paessler Support]



Hello - This is my exclude filter but it does not filter the messages: (severity[6] AND message[%FMANFP-6- ]) but it does not work. I want all the syslog messages which start with %FMANFP to be excluded.

Created on Jun 25, 2020 3:28:22 PM



Would using only FMANFP work as well? The filter does a substring search and it may be sufficient to check for that?

Created on Jun 26, 2020 6:41:24 AM by  Stephan Linke [Paessler Support]

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