[c-nsp] mpls and etherchannel

[Lukas Tribus]

> Per-packet load balancing is one of two options; the other being "adaptive". 
> 
> Adaptive was meant to fix the actual problem we are using per-packet to 
> solve, which is cases where spray of packets across the member links is 
> unequal. The adaptive mode was developed to dynamically realize and fix 
> this. Unfortunately, it doesn't work when the payload does not lend 
> itself well to LACP hashing. 
> 
> So per-packet mode to the rescue. 
> 
> By the way, only supported on routers (confirmed on MX Trio, as it's 
> all we have). Not supported on the EX switches (which doesn't matter, 
> as those do a good job of LACP hashing, since the payload is 
> predictable). 
> 
> I've asked Cisco to develop a similar capability, as it would make a 
> world of difference in our environment, technically and commercially. 

What you can do on the 9k is manual hash shifting [1], but if the
underlying hash sucks, it won't really solve your issue I guess.


Lukas


[1] https://supportforums.cisco.com/document/111291/asr9000xr-loadbalancing-architecture-and-characteristics#polar