Per Packet loadbalancing

[nathan.deane]

Hi,

I have 2 x ADSl lines and wish to utilise them at the same time but due to problems within the carrier i cannot use MLPPP.

I will be terminating them on the same router and would like to use some kind of Per-Packet load balancing but when i checked the feature navigator was surprised to see that PPLB is only supported on 10000 and 12000 series ?!?!?!

Am i going crazy or is this not the case, i am sure there is a similar feature that is available on the lower end routers ...ie 1721 but cannot find it

any help is appreciated

Thanks

Nathan

[thisisshanky · Accepted solution]

Per-packet load balancing, can create out of order packet delivery, which can cause issue with some apps. Your best bet is to use two static routes with same admin distance,

ip route 0.0.0.0 0.0.0.0

ip route 0.0.0.0 0.0.0.0 and use CEF.

[nathan.deane]

Thanks for the reply.

I read this answer in another post and wondered how this combats packets being created out of order ? is it because it is based on a session ?

also, just to know for my own knowledge, can per packet be done on low end routers ?

Thanks

[thisisshanky · Accepted solution]

I have not tried that command on a 1700, but I have tried it on a 2600.

Also I could find some references which explain the problems associated with per-packet LB.

http://www.swcp.com/~jgentry/cisco/cisco-load.html

If you search on this forum, you should find more references related to the same.

Typically it would be better if your ISP can also configure per-packet load-sharing so that incoming traffic to your network will also be load balanced.

Still, the destination end's TCP stack (For TCP apps), will have to buffer and reorder the incoming packets, (if they come out or order, which is very likely).

[nathan.deane]

Thanks for your help

It should not be a problem to get a bespoke load balancing config from my ISP....

this has all started with a problem with using MLPPP over a contended DSL network.,.. annoying!!

[afilandro]

nathan,

I think it is supported on any platform

We use it on several different routers--3640 and 3745 w/12.2(3d) and 12.3(10c) code, granted its

frame relay..but it should still work w/ADSL

ip cef on the router

and

ip load-sharing per-packet on the subint

In regards to out of sequence packets, it is probably not a good idea to run any type of picky traffic..because it is possible that some stuff might go asymetrical. We have been using it for FTP transfers for several years to load balance a "1server to 1server" communication over 2 circuits...looking at monthly performance reports of both circuits, the load is almost exactly evenly balanced...but per-flow is usually the better way to go if you can.

[nathan.deane]

Thanks for the reply,

The traffic is just file transfers acros an MPLS network and Internet browsing

nathan