[cisco-nas] Offload PPPoE processing from DSL aggregation 7206 toanother 7206?

[Oliver Boehmer (oboehmer)]

Scott Lambert <> wrote on Thursday, July 20, 2006 1:40 AM:

> I have about 1000 PPPoE users on an 7206vxr with NPE400.  The CPU
> load is at about 75% according to the MRTG 1 and 5 minute averages.
> According to sho proc cpu, the load is much higher than that for tens
> of seconds at a time.  I'm thinking that is about as high a load as I
> want on a router.

Right, looks too high.
Are you terminating PPPoE (over ATM) directly on the box, or are you
terminating PPP sessions forwarded to you via L2TP?

> 
> I have another 500 users I need to migrate over from aquisition of
> another ISP.  My connection to the Telco is an OC3 and the migrated
> user will be brought in over the same OC3.
> 
> I figure I have two options.
> 
> 1) Buy an NPE-G1.
> 
> 2) Figure out some way to hand off PPPoE processing to another 7206VXR
>    with an NPE-300.
> 
> I apparantly have not yet found the correct search terms to locate any
> documents showing me how to do option number 2, or it isn't possible.

well, if you receive the sessions via L2TP, you could ask the Telco to
send the 500 users to another IP address, i.e. your NPE300. The packets
would still travel through your box, but the load will be less as the
NPE400 doesn't need to do any L2TP decapsulation, it just needs to
switch the IP packets towards the NPE300. As I don't think you have any
more CPU to spare on the NPE400, I think you need to go with a faster
hardware.

If you terminate the PPPoE sessions directly, you definitly need a
faster hardware. You could still forward the sessions via L2TP, but this
will not really decrease the load compared to if you terminated them
directly..

	oli