Layer-1 ish question

[7rbowenii]

I am trying to understand the signalling that a port goes through when a connection is made.

The problem I am seeing is this:

In an HA config server, I have two physical connections. One to access switch A, and one to access switch B. These remain in a hot/warm backup mode. if the hot goes down, the warm takes over mac information for the connection. When the hot comes back up, the hot resumes its role and regains the mac.

The problem I am seeing is on a switch reboot. If I reboot the hot side, the warm side takes over. But, when the hot side switch comes up, there is initial signalling that convices the server that the connection is good and a role swap is intiated. However, the link immediately goes back down and the server is in a hung state. When the connection comes up and is 'good' for the hot side, the active session stays on the warm connection.

I hope I've given enough information. Any help would be appreciated. I am using Cisco 2970s ver 12.1(19)EA1d and IBM etherchannel.

Thanks in advance.

-Bo

[benhur.p]

Any update on this?

[Terry Pattinson]

To be sure that I understand this, the link goes down on the server side or the switch side? As for signalling that the port normally goes through initially, it uses a Fast Link Pulse (FLP) to determine the capabilities of the port. This occurs once the carrier has been imposed on both the receive and transmit pairs.

http://www.cisco.com/warp/public/473/46.html#maintain

http://www.cisco.com/warp/public/473/3.html

HTH,

Terry