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Monitoring up/down of ports



I have an ISA570 firewall setup with 2 internet connections coming in. I have both ports being monitored in PRTG. Once in a while I get a line that goes down, but PRTG never seems to recognize the connection as down. It seems to only show the connection as down when the port is physically disconnected. To find the connection, I normally have to manually refresh the sensor and look for "IN" traffic to be 0kb. This is how I know which line is down. Currently, I just had Errors In & out selected under Traffic specfic and now I enabled Discards In & Out, not sure if that will help. Let me know.

Thanks in advance.

cisco monitoring no-notification ports up-down

Created on Mar 24, 2014 6:21:26 PM

1 Reply




thank you very much for your KB-Post. If line down, here means that the connection is not physically down, but essentially not showing traffic, then I would suggest to set an Error-Limit on the sensor, for traffic "near to 0". This can be done in the Channel Settings of the Sensor.

best regards

Created on Mar 26, 2014 2:12:39 PM by  Torsten Lindner [Paessler 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.