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Down sensors flapping between Down ended (now: Unknown) and Down (before: Unknown)



Hi folks,

Lately I have seen an increase in our environment of down snmp sensors constantly flapping, rather than providing a simple down notification email. The status seems to go between Down ended (now: Unknown) and Down (before: Unknown)

On the error message e-mail, we get:

Error caused by lookup value 'Idle' in channel 'State'

On the unknown status e-mail, we get:

'No data since [time redacted]'

The switches being monitored are a combination of Cisco Catalyst 4500 on 3.11.04 and Cisco Catalyst 9800 UXM on 17.3.2r

This seemed to start happening out of the blue sometime in the past month or two, possibly with a PRTG update. Has anyone noticed this?

Thank you in advance, -Travis R.

cisco prtg snmp

Created on Aug 14, 2023 7:59:22 PM

1 Reply



Hello Dear customer,

Thank you for reaching out to us regarding the issue you're experiencing.

To ensure that your concern receives the dedicated attention it deserves, we kindly recommend opening a support case with us. Our team at [email protected]. By opening a support case, you'll benefit from a streamlined communication process and personalized solutions tailored to your situation.


Created on Aug 15, 2023 5:57:23 PM by  Ricardo Sanchez [Paessler Technical 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.