I will appreciate if someone can assist with an issue I have been experiencing using a Cisco 1841, with SNMP. I have a monitoring server running MRTG and has configuration to poll data from the router via SNMP and it does not work. It does not seem the router is sending the SNMP information at all. Below are the configuration details,
1. Server run on internal IP 10.0.0.X. It also uses a public IP, so the internal IP is translated to the external IP via a NAT static rule on the firewall.
I have other entries on the mrtg file in the server which data is being collected without a problem.
2. The Router on the other end is a cisco 1841, Cisco IOS, (C1841-ADVSECURITYK9-M), Version 12.4(3g).
SNMP Configuration as follows, (excluding Password and Full IP on ACL 1)
access-list 1 permit 203.39.64.XX
snmp-server community <password> RO 1
snmp-server ifindex persist
This is the output of the 'show snmp' in the router,
0 SNMP packets input
0 Bad SNMP version errors
0 Unknown community name
0 Illegal operation for community name supplied
0 Encoding errors
0 Number of requested variables
0 Number of altered variables
0 Get-request PDUs
0 Get-next PDUs
0 Set-request PDUs
0 Input queue packet drops (Maximum queue size 1000)
0 SNMP packets output
0 Too big errors (Maximum packet size 1500)
0 No such name errors
0 Bad values errors
0 General errors
0 Response PDUs
0 Trap PDUs
It seems to me as the router is not sending any SNMP data at all. I have configured the configuration in both end for many times and I can't still figure out why it's happening.
It very well could be blocked by the ISP. Any device capably of filtering between the manager and the agent could be blocking the traffic. I agree that it looks like this particular ASA is allowing it.