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Cisco SG300 SNMP monitoring breaking https




Apparently PRTG's implementation of SNMP is causing Cisco SG300's to stop responding on HTTPS. In my experience this issue also causes the switch to have problems when a reload command is issued and eventually you just have to pull the plug.

I still have an open case with Cisco but they seem to be implying its Paesslers problem so I thought I would open a case here as well. Is this a know problem and is there a fix? I have a lot of these switches currently effected by this issue.

bug cisco prtg snmp

Created on Feb 13, 2019 1:21:28 PM

1 Reply



Hello there,

So far I did not find any similar reports from other customers. The ticket on Cisco's end doesn't really contain much details like which SNMP version is involved and alike. For example SNMP v3 uses encryption, which could play a role here, otherwise I don't really see how unencrypted UDP packets used by SNMP should bring down the SG300's HTTPS connectivity. Other aspects that can be tweaked on PRTG's end would be trying out "SNMP Compatibility Options" on the device's "Settings" tab in PRTG, for example changing the request type and setting a delay for SNMP queries, to see if this makes a difference.

Kind regards,


Created on Feb 14, 2019 12:45:58 PM by  Erhard Mikulik [Paessler Support]

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