[c-nsp] etherchannel load-balancing & WS-X6708 issue

[Nick Hilliard]

On 09/09/2011 12:33, Jiri Prochazka wrote:
> Primary box is 6500-1 (several hunderd Vlans and SVI's) and under standard
> circumstances Po1 is the only path utilized, but even if I freak out, I am
> not able to push more than aproximately 25 Gbps from 6500 over Po3 to
> edge-2. My initial guess was bad port assignment and therefore not utilized
> local switching..

what is the output of: "show etherchannel load-balance"?  Also, is the port
channel between 6500-1 and 7600-1 configured as a switch port or as a
routed port?  This makes a very substantial difference in how traffic is
load balanced over the bearer links.

> The major problem which I can not beat (and maybe it's a dead end for me) is
> the system how IOS decides which ports will be assigned to 0-7 ID's used in
> etherchannel load balancing algorithm. As I observed, it absolutely depends
> on a sequence of adding/removing ports from/to an etherchannel.

Have you played around with the "port-channel hash-distribution" command?
This may help to make the ID assignment more consistent, even if you don't
have full control over everything.

Sounds like you may just have too much traffic for your hardware
configuration to make it work reliably.

Nick