IMA group flapping.

[darrenj]

I have a 3640 router router running software code 12.0(5)XK1, and the WAN link is compromised of 2 x 2MB ATM links that form an IMA group. The problem is that under heavy load, and at approximate 1 hour intervals, the group loses 1 of the ATM links, then the other link drops which means the IMA group has no active links. Obviously, the customer cannot transmit traffic at this time. Then both links re-appear and the IMA group is reformed. This all happens in about 5 seconds.

Does anyone know why this may be happening? The circuits have been checked. Hope someone can help?

Thanks,

Darren.

[#2]

You can check the bug CSCdu38436. And also check with the Telco.

Inverse Multiplexing Over ATM on Cisco 7X00 Routers and ATM Switches

http://www.cisco.com/warp/public/121/paima.html

[beng]

You need to check your "IMA Differentiate delay" parameter, ensure you configured for the maximum, such as 250. You may also move two T1 to another two ports and to see if the problem following the circuit?

Regards,

/Bessie