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SNMP error # -2003 after probe upgrade



After upgrading the probe device from Server 2003 to Server 2008 R2, some of the custom SNMP sensors on the LAN are returning error -2003. I have tested using Paessler SNMP Tester 5 and receive the same result. When I try to select the option to just "Read Device Uptime" it also fails.

- The Windows firewall is not enabled on either the probe or the target machine. - The new server is sitting on the same IP address as the old server, so firewalls are not an issue anyway

Any idea what changing out the probe device would do? Is there a piece of software that needs to be installed on the probe that we didn't install?

prtg snmp windows-2008

Created on Apr 24, 2013 1:50:33 PM

1 Reply

Accepted Answer



First of all please check if the SNMP Settings (Version, Community String, port, eventual authentication, etc.) are correct.

Please also check if PRTG (or the PC on which PRTG is installed) is allowed to send SNMP Requests to the device in the SNMP service on the target.

Lastly, make sure that the SNMP service is installed on the probe device.

If the SNMP tester is not working, then there is something blocking the traffic to the Probe device.

Created on Apr 24, 2013 7:13:52 PM by  Greg Campion [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.