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Monitoring Switches



I am using PRTG v8 and PRTG Traffic Grapher to monitor DELL switches in my office. A number of my switch ports go up and down all day. They are down for only a few seconds according to the email trail but it offers concern to me that there may be a larger underlying problem in my network.

State: DOWN Error: No response (check: firewalls, routing, snmp settings of device, IPs, SNMP version, community, passwords etc) Group: Core Switch

Sensor: Port 650 (802.1Q VLAN) on Core Switch (

Current Total: 0 kbit/second Date: 10/22/2010 11:53:42 AM

Is there a possibility that this error not caused by PRTG having issues with communication? Or can I be confident that there is a problem that I need to resolve.

Seems to be random ports that are failing but failing on a regular basis.

Thanks for your help with this.


fail prtg-traffic-grapher switch

Created on Oct 22, 2010 4:05:29 PM

3 Replies



Dear Tristan,

where do you see these errors? In PRTG 6 or PRTG 8? Or both? Of course the issue might be something blocking the communication as mentioned in the error-message itself (firewalls, routing) or it may be also the individual target device, not being able to respond (in time). There you could try enabling (if not already enabled) the 'Retry'-Option (SNMP Compatibility Options) or try a higher SNMP Timeout.

Best Regards.

Created on Oct 25, 2010 12:14:34 PM by  Torsten Lindner [Paessler Support]



I agree, try a higher SNMP Timeout to 30 AND it will work!

Created on Jul 8, 2016 7:21:07 PM



This worked for us..

1) Try a higher SNMP Timeout to 30 AND it will work! 2) If is a Windows OS check the services contacting the OIDs (i.e. HP's Insight Manager or Dell's Open Manage).


Created on Jul 8, 2016 7:23:10 PM

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