Etherchannel a Trunk

[wrwiii122]

I have two 3550's connected, trunking 802.1q, using fiber. I want to install a wireless link for a backup but dont want to manually bring it up and down because I want the fiber trunk to be primary and the wireless secondary. Someone told me to use priority but I was thinking about etherchannel. Can I use etherchannel on a fiber port and copper port trunking? If so can someone give me an example. Thanks in advance.

[jackyoung]

It should be limited by the phtsical media, i.e. Copper and Fibre should be able to create an Etherchannel. However, is it a point-to-point connection between two 3550s.

Do you mean the copper will be connected via the wireless link ? If yes, only if the wireless link perform the same delay w/ your fibre link then it will works theorically. However, the Etherchannel will load-sharing two links, if the wireless is not stable and not the same delay w/ fibre, it will create the problem.

I recommend not to use Etherchannel, and enable the L3 routing or make use router to make the wireless link as backup link (e.g. floating static, etc.).

Hope this helps.

[wrwiii122]

Well I found out that you can not use etherchannel on two different speeds. One link was 1000M and the other is 100M and it shut down the etherchannel port because if it. But the funny thing is that it let me configure it like that and set it up like that.

Is this true that the speeds have to be the same? If so I need to see if I can set the GBIC to 100M. I need these two links for automatic failover.