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sensors status down



Hi all,

i have created a sensor on my Router (cisco 2800 series) for snmp traffic it was going well, but we made an upgrade of the Internet Bandwith from 2Mbps to 4 Mbps and since then, the sensor is down. the error message is: check:firewall, routing,snmp settings of device,IP, SNMP version, community, password etc...)(SNMP error#-2003).

bandwidth-monitoring firewall snmp-traffic

Created on Jul 2, 2013 3:07:46 PM

5 Replies




thank you very much for your KB-Post. Can you please try adding the sensor anew (for a test)? Does the new sensor then work?

best regards.

Created on Jul 3, 2013 8:51:08 AM by  Torsten Lindner [Paessler Support]




thank you for your suggestion. I have tried adding the sensor again on my router but i received the same error message: No response (check:firewall, routing,snmp settings of the device,IPs, SNMP version, community, passwords etc) and other information that i can add is that we have configure behind the router a CISCO ASA 5505 series appliance on which we setup a Site to site VPN connection and firewall rules; of course making sure that port 161 is opened for SNMP communication. best regards,

Created on Jul 3, 2013 1:46:20 PM



May I ask you to please use our SNMP Tester, preferably the new betaversion of the Tester 5, to perform a "Read Device Uptime" against the target device? Which results do you get in the Tester? Please send us the result logfile from the Tester.

Created on Jul 4, 2013 1:15:26 PM by  Torsten Lindner [Paessler Support]




find below the log file as requested thanks,

----------------------- New Test -----------------------
Paessler SNMP Tester 5.0 (Beta11)
7/4/2013 5:39:14 PM (1 ms) : Device:
7/4/2013 5:39:14 PM (2 ms) : SNMP V1
7/4/2013 5:39:14 PM (2 ms) : Uptime
7/4/2013 5:39:16 PM (2098 ms) : -------
7/4/2013 5:39:16 PM (2099 ms) : Value: No response (check: firewalls, routing, snmp settings of device, IPs, SNMP version, community, passwords etc) (SNMP error # -2003)
7/4/2013 5:39:16 PM (2100 ms) : Done

Created on Jul 4, 2013 4:41:42 PM

Last change on Jul 5, 2013 7:51:12 AM by  Torsten Lindner [Paessler Support]



This means that a general SNMP connection is not possible. Something is blocking the connection. Or the SNMP Settings are wrong, so that a connection is not possible. Or the host where the SNMP Tester and/or PRTG is running, is not allowed to send SNMP Requests.

Created on Jul 5, 2013 8:03:48 AM by  Torsten Lindner [Paessler Support]

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