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802.1q or dot1q native vlan no snmp data



An SNMP sensor setup against a Cisco router sub-interface returns no data, even though there is data traversing that interface. I believe this is because the sub-interface is configured as the dot1q native VLAN.

Does anyone know whether this is a bug/know problem with PRTG and whether it has been fixed in a more recent version?

Details: interface Ethernet0

interface Ethernet0.200000 description SNMP Sensor 1 - No Data encapsulation dot1Q 200 native

interface Ethernet0.200201 description SNMP Sensor 2 Shows Data Correctly encapsulation dot1Q 201

interface Ethernet0.200202 description SNMP Sensor 3 Shows Data Correctly encapsulation dot1Q 202

I am using PRTG version

802-1q dot1q native snmp sonicwall vlan

Created on Sep 2, 2011 12:13:01 PM

Last change on Nov 15, 2011 4:34:49 PM by  Daniel Zobel [Product Manager]

5 Replies



Simon, have you found a resolution to this problem? I'm having the same type of issue montitoring Layer 2 802.1q Virtual LAN interfaces with a SonicWALL e5500 firewall. SNMP shows "ok", but no traffic stats at all. I posted a reply to a similar post from another Sonicwall user, but no replies yet.

Created on Nov 14, 2011 3:43:26 PM

Last change on Nov 15, 2011 4:35:06 PM by  Daniel Zobel [Product Manager]



I have the same Problem with sub-interfaces in PRTG.

Created on Feb 2, 2013 8:29:18 PM



we will have a SonicWall in our test lab soon so that we can take a look at the issue

Created on Feb 3, 2013 8:12:38 AM by  Aurelio Lombardi [Paessler Support]



We are still having this issue on our cisco C2951 router.

You can select the interfaces in the adding sensor phase but then all the sensors once added say no such interface.

Has there been any resolution on this?

Created on Jul 11, 2014 9:27:18 PM



We were able to create a VLAN on our Sonicwall here and were able to create a sensor in PRTG for the Sub-interface and the sensor was able to show the correct amount of traffic that was travelling through the VLAN. If you are still having issues with this, please write us an email to [email protected] and we can work on this together. Please mention this KB article as well so we can reference the case and post the solution.

Created on Aug 26, 2014 1:18:16 PM by  Greg Campion [Paessler Support]

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