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New Member

Intermittent routing on 3640

I am having trouble with my Cisco 3640. I have a 1E2W card in it. In that I have 1 T1/FT1 card connected to verizon with PVCs for various DSL connections to end users.

I have Eth0 connecting to the Internet.

I have Eth2 connecting to a switch with other web servers.

I have Serial 2 set up with Sub-interfaces, each being a separate DLCI for each PVC coming in to the T1/FT1 card from verizon.

I have bridged all sub-interfaces from Serial2 along with Eth2. Each interface is ip-unnumbered and BVI1 has an IP.

My problem:

From a system at the end of a PVC (a home dsl connection) I can ping the BVI ip (this is xxx.yyy.zzz.1 and is the gateway for all DSL connections and everything on the switch Eth2 is connected to). Now it is getting intermittent (as in every few minutes!!) that I can ping the ip for Eth0. Everything stops routing that is coming in from Serial2. Everthing coming in from Eth2 is fine.

If I wait a few minutes, I can again ping Eth0 from any Ser2 connection.

I have been running this configuration for over a year with no problems. Nothing new on the configuration has occured. I can always get to the systems connected via Eth2 from those connected via Ser2, I just cannot always connect out to the internet or even ping Eth0 without interuption.

Any ideas here? Thanks!

Brian Andrus

New Member

Re: Intermittent routing on 3640


Just to get things straight, you have configured a virtual interface associated with the bridge, the bridge connects the serial sub-interfaces and the e2, and you have also configured the bridge to route ip packets. Right?


New Member

Re: Intermittent routing on 3640

Exactly how I have it.


New Member

Re: Intermittent routing on 3640


Well, I really don't have a definite answer but what I'm thinking is a problem of excessive multicast or broadcast traffic that can cause input and output queues to overflow,you can verify this by the "show interface".If that was true, then you might need to configure priority queuing or increase the queue size.

Good Luck

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