2811 and 2821 routers-tcp connection timeout

[billkemmer]

Hello,

I just connected 2 sites using a 2821 and a 2811 to connect via a point to point T1. Customer used to do his backups between the sites over the internet, but now wants to use the point to point link. The backups are failing and the vendor is saying that we need to bump up the tcp connection timeout on the routers. Can someone point me in the right direction as to how to determine what this timeout is currently and how to bump it up? Thanks.

[Joseph W. Doherty]

Routers don't, I believe, have settings that determine other host transit traffic TCP timers. Also believe, many hosts might not allow easy or any modification of such timers.

If TCP connections are failing on your new p-2-p T1, I would check for excessive latency and/or errors. Both, I believe, can cause a host to consider a TCP session so bad the TCP session is reset or dropped.

PS:

If you're using FIFO on the WAN interfaces, you might want to switch to FQ. The latter tends to make multiple flow performance more predicable which can assist host TCP session monitoring since part of its operation is based on tracking RTT.