[c-nsp] How does IOS do loadshaing with ECMP?

[Sukumar Subburayan]

On Mon, 20 Nov 2006, Baek, Steven A (US SSA) wrote:

> Would the route processor have stateful tracking to ensure the packet
> coming across the wire takes the same route back?

Nope. The forwarding lookup is based on destination prefix.
>
> If there were two paths to a remote destination, would the rp know which
> path was available and which one isn't?

It would know upto the next-hop (based on adjacency information). Not 
end-to-end.

>
>
> Steve
>
> -----Original Message-----
> From: cisco-nsp-bounces at puck.nether.net
> [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Sukumar
> Subburayan
> Sent: Monday, November 20, 2006 9:00 AM
> To: Phil Bedard
> Cc: cisco-nsp at puck.nether.net
> Subject: Re: [c-nsp] How does IOS do loadshaing with ECMP?
>
> Sup720 supports load-balancing using src_ip,dst_ip+universal_router_id
> and
> this is the default.
>
> In this particular case below, you have:
>
> mls ip cef load-sharing full simple
>
> 'mls ip cef load-sharing full' lets you use 'src_ip,dst_ip+l4 ports'
> instead of the univeral_router_id
>
> However, the addition of 'simple' keyword, allows hardware to use
> the same number of adjacencies as in the IOS CEF adjacency.
>
> Without the 'simple' keyword the HW installs additional adjacency
> entries
> to avoid platform polarization.
>
> sukumar
>
>
>
> On Mon, 20 Nov 2006, Phil Bedard wrote:
>
>> That command tells the box to use L4 port information in making load
>> balancing
>> decisions.   I think if you just set that back to the default it will
>> only use
>> the source/destination hash like you are used to.
>>
>> Phil
>>
>>
>> On Nov 20, 2006, at 9:45 AM, Joe Shen wrote:
>>
>>> mls ip cef load-sharing full simple
>>
>>
>>
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