Router locking up........

[BigDawgFelton]

Hey guys,

I am going to post this with only about half of the information needed to solve the problem but I just want to get the question out there. I don't have access to my config at the moment and I haven't had a chance to get to the console of this router as of yet.

A little background info:

This is a Cisco 1941 router in which I have multiple NAT inside interfaces for internal VLANs. Before my current problem I was using one NAT outside interface for Internet access with another NAT outside connecting to our corporate network that was in a shutdown state.

The router is performing router on a stick and had layer 3 subinterfaces for each VLAN. I have ACLs filtering on each subinterfaces allowing only the traffic I need through.

I also currently only have one static NAT port for an FTP server.

The time finally came when I had to connect our corporate network to this router via an access port on a 2950 which trunks to the router.

The problem comes when I send any traffic to the subinterfaces on the corporate network which is the second NAT outside interface on the router. The main point for this connection is to do a static NAT from this interface to a web server on another VLAN. Any traffic to this interface including just pinging from the outside causes connection to the router to fail for about 3-4 min.

Like I said I haven't ha the chance to get to the console yet Sony cant tell everything that happens. Nothing shows up in the logs after I can get connection back and the router didn't reboot as a "show version" says the router has been up for a long time.
The CPU is also usually very low as not that much traffic flows through this router at a time.

I built a very similar network in packet tracer and it works just fine.

Does anyone have any ideas of what might be going on? It will be nice to have some directions when I fleet the chance to troubleshoot this.

Thanks in advance!!

Elton

Sent from Cisco Technical Support iPhone App

[Muhammad Thanveer]

Dear Elton,

I believe that your hardware is fine.

I had more or less same kind of issue and I solved it by doing speed auto and duplex auto. Why don't you just check it.

Regards
Thanveer
"Everybody is genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is a stupid."