[c-nsp] x6148 vs. x6548

[Pete Templin]

Geoffrey Pendery wrote:

> I have a question of my own, since this subject has come up a time or
>  two - regarding the 6148's, the statement is made a couple times
> that Etherchannel will get you port redundancy but no extra
> bandwidth, since the ASIC is only a gig.  But if I distribute my
> channel across two slots, say Gig 1/1 and Gig 2/1, does that get me
> around the gig limit?  Or even Gig 1/1 and Gig 1/48, since it's
> separate ASICs? Logic tells me yes, but I've heard the "1 gig limit"
> mentioned as if it's a hard platform limitation, not just a result of
> a particular bottleneck.  My instinctive behavior with channels is to
> span them across blades anyway, to guard against blade failure....

My understanding (since my google-fu won't find a quickie answer at the 
moment) is that 6148s copy any EtherChannel frames to every ASIC on the 
card, so you can get to 2G by spreading over two cards, but you're still 
limited to 1G no matter no many controllers you cover within a 6148.  :(

We've updated the banners on all relevant 6148-loaded chassis to remind 
folks to never build EtherChannels on those cards.  Oh well...

pt