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cisco switch ports not detected using auto discovery



When running the auto-discovery on a stack of 6 Cisco 3750's, several of the active ports were not recognized or added to the list of sensors for that device. Rerunning auto-discovery did not add the switch ports either.

How can I correct this and get the switches added.

auto-discovery cisco-3750 switch-port

Created on Feb 3, 2011 6:07:14 PM

6 Replies



Dear Mark,

just to check, can you add sensors for those ports manually? Please also check if the option "Skip Auto-Discovery for known devices/IPs" is enabled in the group where the Auto-Discovery takes places.

Best Regards.

Created on Feb 3, 2011 6:22:42 PM by  Torsten Lindner [Paessler Support]



Hello, I encounter maybe a similar issue for different models of Cisco switches ( 3560, 9300, 3850 ). When using auto-discovery , the ports are discovered but the port number is not displayed. Instead of Gi1/0/5 for example I see 10105. this feature used to work with previous versions of PRTG.

Created on Oct 15, 2019 9:53:24 AM



Hi there,

We have addressed this issue in the latest release:
SNMP Cisco System Health sensors get correct names and units again after sensor creation. In previous versions, all channels except for the first one were only named by the index of the OID in certain cases.

Best regards.

Created on Oct 15, 2019 10:13:16 AM by  Dariusz Gorka [Paessler Support]



Hello Dariusz,

Thank you for your advice. I am running PRTG Network Monitor x64. so auto-discovery does not work anymore for cisco switches ? I must use a specific sensor for each cisco device? kind regards, Felix.

Created on Oct 16, 2019 9:18:18 AM



Hello Dariusz, I have upgraded the PRTG server to version and still get the same problem: the port numbers are not displayed correctly when doing an auto-discovery on a Cisco switch. Instead of seeing interface Gi1/0/5 for example I see 10105. This feature is working fine on a very old version of PRTG ( version 9 ).

I would appreciate your help for this incident. thank you. Kind regards, Felix.

Created on Oct 16, 2019 12:06:07 PM



Hi Felix,

I'll contact you via mail, since it's easier to handle those cases there.

Kind regards,
Birk Guttmann, Tech Support Team

Created on Oct 16, 2019 12:27:18 PM by  Birk Guttmann [Paessler Support]

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