Ether Channel + STP

[lifebook567]

6. Ether Channel is a prefer method in combination with (spanning tree protocol) STP? Always? Is there any scenario that better use only STP without Ether Channel even there is more than one link?

[fmeetz]

Actually is Ehterchannel an enhancement of STP.In STP if a forwarding link fails then whole topology changes.This takes few time to converge.Instead if you have an Etherchannel multiple even if the link fails traffic takes alternate link within the Etherchannel without the need for topology change.Always Etherchannel would be better.

[devang_etcom]

hi...

if you have two switch connected with each other using the multiple link then it will be good to understand the etherchannel and STP...

whey you are talking about the STP... and have multiple link to the other switch... then STP willl block the one link if there are two link... it means FTP will calculate the root brige, root port, designated port...etc... so here you are not utilising the infrastructure...

but when ever we are talking about the etherchannel in redundunt link topology...then etherchannel will make a bundle of the all the redundant link and all links are treated as a one logical big pipe/bandwidth link... so here you are not having blocking kind of things so you are utilising your whole the resources...so here you can have loadsharing also between redundantlink....

rate this post if it helps

regards

Devang

[Francois Tallet]

Yes, basically, the etherchannel is handled at a lower level than STP. That's why LACP is actually an 802.3 standard, not 802.1 (well, actually 802.1 is taking over LACP;-)).

So from the STP perspective, a channel is a unique link, that's why STP does not see the redundancy that is provided at the link level.

Regards,

Francois