[nsp] load balancing over parallel DSL lines

Mark E. Mallett mem at mv.mv.com
Thu Nov 20 16:47:39 EST 2003

On Thu, Nov 06, 2003 at 02:44:37PM -0500, Mark E. Mallett wrote:
> Hi-
> Wondering if anyone has success in doing load balancing over DSL
> destinations backhauled via ATM.  Given RBE setup including this:

I wanted to follow up on this in case anyone was interested.
My question was how to get per-packet load balancing done over
multiple DSL lines aggregated via RBE.  It's now working, and
I'm sorry to say that I don't know the exact magic that did
the trick.  I was, stupidly, misled by this sort of output:

> gw> show ip cef <subnet> internal
> <subnet>/xx, version 94, per-packet sharing
> 0 packets, 0 bytes
>   via <ip1>, 0 dependencies, recursive
>     traffic share 1, current path
>     next hop <ip1>, ATM1/0.302 via <ip1>/32
>     valid glean adjacency
>   via <ip2>, 0 dependencies, recursive
>     traffic share 1
>     next hop <ip2>, ATM1/0.302 via <ip2>/32
>     valid glean adjacency
>   0 packets, 0 bytes switched through the prefix
>   tmstats: external 0 packets, 0 bytes
>            internal 0 packets, 0 bytes
>   Load distribution: 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 (refcount 1)


I was (erroneously, I guess) thinking that this was telling me that
packets were only taking one of the paths.  In the output above, the
"current path" note is only attached to one destination, and the
alterating 0s and 1s seemed to be confirming that only one
path was selected.  Can anyone enlighten me on the true meaning?  

We had been monitoring the far-end router and initially packets were
only coming in on one interface.  I'm afraid I never checked that
again until recently, because the above "show ip cef internal" output
never changed on our side.  

Thanks for the suggestions and interest.


More information about the cisco-nsp mailing list