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CPU sensor disappeared

Votes:

0

Hi,

up until yesterday my Cisco 3850 switch had a CPU sensor working fine. Now it's red, with all the other sensors being fine (green). When trying to add again, it doesn't appear as an option under Cisco Heath Sensor. No device config changes, uptime on switch over 1 year. Can you please explain what happened?

can-not-add cpu-sensor disappear

Created on Jun 19, 2017 10:09:07 AM



8 Replies

Votes:

0

Hello silavric,
we appreciate your contact.

This most likely means that the data that was originally available is no longer available.

This can either happen due to a software bug on the switch. In this case try to restart the device, check whenever you're able to deploy the sensors afterwards. You may also want to check if there are software updates available for the switch and install them if available.

This can also happen if the device's configuration was changed, it's possible to make only specific SNMP OID's available (instead of everything). This can affect the way SNMP-based sensors work.

All of the above is assuming that you're running the latest PRTG Version (17.2.31.2153 at the time of this writing).

If that doesn't work out, feel free to contact us via E-mail at [email protected] and refer to this KB-Post, we can assist you further from there.

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Jun 19, 2017 11:46:48 AM by Luciano Lingnau [Paessler]



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As per my previous post, no config changes. None on the switch, none on our PRTG server. Scheduling restart, will update.

Created on Jun 21, 2017 8:48:57 AM



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It happened again, still the only solution so far is restart. If anyone has an idea that doesn't involve production downtime please reply.

Created on Sep 12, 2017 8:56:02 AM



Votes:

0

Hello silavric,
thank you for your reply.

  • Is PRTG running the latest available version?
  • Is the switch running the most recent available firmware?

If the sensor's come-back when restarting the device, something must be wrong with the device. You could try to restart the device's SNMP agent only (instead of the whole system) to avoid downtime. But I strongly encourage you to contact the vendor if this is the case, since they may be able to adjust the stability of the SNMP implementation on the device.

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Sep 12, 2017 11:25:15 AM by Luciano Lingnau [Paessler]



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0

All the other sensors on that device work just fine. We had an event with all the sensors going down, and after it was solved the cpu sensor never recovered, even more, if you want to add it again, there is no such option anymore.

Created on Sep 12, 2017 5:22:36 PM



Votes:

0

Hello silavric,
thank you for your reply.

And what about the involved software versions?

  • Is PRTG running the latest available version? What precise version is installed/running?
  • Is the switch running the most recent available firmware? What precise version is installed/running?

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Sep 13, 2017 9:00:57 AM by Luciano Lingnau [Paessler]



Votes:

0

prtg serverPRTG Network Monitor 17.3.32.2339+
switchCisco IOS Software, IOS-XE Software, Catalyst L3 Switch Software (CAT3K_CAA-UNIVERSALK9-M), Version 03.03.05SE RELEASE SOFTWARE (fc1)

Created on Sep 13, 2017 12:11:17 PM

Last change on Sep 13, 2017 1:50:34 PM by Luciano Lingnau [Paessler]



Votes:

0

Hello silavric,
thank you for your reply.

There appear to be several newer software versions available for the switch. Please refer to:

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Sep 14, 2017 1:20:37 PM by Luciano Lingnau [Paessler]




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.