Monitor Cisco ASA5510 via SNMP

[pcfixerhough]

I am trying to setup our ASA5510 so that I can monitor it with MRTG, Cricket, CyberGuage (basically anything that will do it via SNMP). I do not want to permanently hook up the management interface to a network port so ideally I would like to do it via the internal ethernet port. When I try to use snmpwalk or one of these monitoring tools to talk to the router I get a timeout message. I have verified that the community string is set and I use the same string on my other hardware that work with these utilities. I have even tried to set the community string to public and it hasn't changed anything. Here is the snmp part of the running config from the router, any pointers in the right direction are greatly appreciated.

snmp-server location Highschool
no snmp-server contact
snmp-server community xxxxxxxxx
snmp-server enable traps snmp authentication linkup linkdown coldstart