[52749] in North American Network Operators' Group
Re: per-packet load sharing in cef or dcef
daemon@ATHENA.MIT.EDU (Feger, James)
Thu Oct 10 09:19:03 2002
Date: Thu, 10 Oct 2002 08:18:21 -0500 (CDT)
From: "Feger, James" <jfeger@feger.net>
To: Adam Atkinson <Adam.Atkinson@damovo.com>
Cc: <nanog@merit.edu>
In-Reply-To: <054E6AB487D5074C9680ED7BA12CBABF0A87F8@uk001s002.d.grp>
Errors-To: owner-nanog-outgoing@merit.edu
I am not sure what is happening for you, but as a general rule of thumb I
don't run per-packet load sharing on circuits that are not 'the same'.
The need for packet re-ordering goes way up when you are running
per-packet on two types of circuit. Are the circuits provisioned for the
same speed at least?
-jf
On Thu, 10 Oct 2002, Adam Atkinson wrote:
>
> per-packet load sharing in cef / dcef just doesn't seem to want to work.
>
> I have two 7500s joined by a frame relay link and a fast ethernet.
>
> Traffic is coming in to one of the 7500s via a third link, and goes
> to a loopback on the second 7500.
>
> I have cef turned on
>
> I have "ip load-sharing per-packet" on every interface
>
> The FR and FE have the same ospf cost
>
> The routing tables and "sh ip cef" agree that there are
> two equal paths to the loopback.
>
> But all the traffic goes over one link.
>
> I've been through Cisco troubleshooting documents etc.
> and as far as I can see, everything is perfect.
>
> Also, a deja search reveals plenty of other people with
> similar problems, and no solutions I can see. Are we all
> missing something obvious?
>
> --
> Adam Atkinson
>
