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New Member

Connectivity Dropping Randomly

I recently changed ISPs which involved setting up and implementing a new router to the outside. I installed a 3640 with 12.3(5).

Background Info:

I have 4 T1s bundled together with PPP Multilink to create a 6M connection. (Serial 1/0-2/1)

Interface Multilink1 has an external IP with a /30 address that connects to the edge of the ISP.

Ethernet1/0 acts at my ethernet default GW with a /27 network address and is plugged into a VLAN on my 6509 that acts as "DMZ"

The only other device plugged into that VLAN is a Linux firewall with two NICs (one plugged into the ISP Vlan and the other on the LAN. The firewall performs all the NAT translations, etc


Since changing ISPs, clients on the LAN that run either MSN Messenger or Yahoo Messenger get logged out of their respective messenging client randomly. I have removed all access-lists on the 3640 router in an attempt to resolve the problem and it still continues.


Re: Connectivity Dropping Randomly

I think some more analysis is required on the router, like flapping links and routes, debugging MLPPP etc.. If they are stable, analyzing the respective sessions with the relevant show/debugs commands might give a clue.

New Member

Re: Connectivity Dropping Randomly

Thanks for the ideas. I actually did some more troubleshooting on the router and found that the router itself was set to debug all. After doing a 'no debug all' the issue stopped occuring.

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