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Some of my SNMP sensors do not work after updating from PRTG 8 to PRTG 9 or later



After updating from PRTG 8.x I have some SNMP sensors that do not work anymore.

All of these sensors seem to have in common that they are located in in the same network segment(s) and my PRTG system / probe system is a multihomed system (i.e. has more than one network card).

outgoing prtg prtg12 prtg9 snmp

Created on Sep 30, 2011 11:54:49 AM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6

Last change on May 9, 2012 12:10:38 PM by  Daniel Zobel [Product Manager]

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Accepted Answer



Important note: The information in this article is outdated. We do not officially support any updates from PRTG 7 or PRTG 8! It is also technically not possible to directly update from these versions to current PRTG versions. We recommend that you perform a clean installation of the latest PRTG version.

Please see PRTG Manual: Update From Previous Versions

With version 9 we have changed the behaviour of SNMP request. SNMP requests are now using the Outgoing IP address setting from the PRTG Probe Administrator application. PRTG 8 did not use the setting, it always used the "auto" setting.

When updating from V8 to the current PRTG version, a previously incorrect setting now becomes apparent.

In order to fix this you must open the PRTG Probe Administrator, select the Outgoing IP Settings tab and select the "auto" setting (or another setting, depending on your network setup).

Created on Sep 30, 2011 11:59:29 AM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6

Last change on Sep 8, 2015 4:20:48 PM by  Gerald Schoch [Paessler Support]

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.