any load-balancing multi-homed solutions?

[shinydonut]

Hello,

Recently, we added 3 ADSL lines to our office to use as our backup WAN, and I was wondering if anyone knew of a solution where I could load-balance the traffic evenly between the three ADSL modems? I'm using a Catalyst 6509 switch with 3 VLANS. Each VLAN uses a single ADSL modem as the gateway, but that solution doesn't provide for load-balancing. The 3 ADSL lines are from different providers, so the solution must account for multi-homing. I've got a spare 7206 router that I can throw into the mix if it was necessary. Can anyone offer a solution to this problem?

Thanks in advance,
Rich

 

[CiscoFreakazoid]

Etherchannel should do the trick for catalyst series switches.
In Catalyst 6500/6000 switches running CatOS, EtherChannel aggregates the bandwidth of up to eight compatibly configured ports into a single logical link. A Catalyst 6500/6000 family switch supports a maximum of 128 EtherChannels. All Ethernet ports on all modules, including those on a standby supervisor engine, support EtherChannel with no requirement that ports be contiguous or on the same module. All ports in each EtherChannel must be the same speed. The load-balancing policy (frame distribution) can be based on a MAC address (Layer 2), an IP address (Layer 3), or a port number (Layer 4). These policies can be activated, respectively using the set port channel all distribution {ip | mac} [source | destination | both] command.

I hope this will answer your question, if you encounter further problems just leave a message here.

Good luck!

Henk
CCNP/MCSE

 

[johnny99]

A classic multihomed setup on 3 lines is not a big problem. It just require your own IP-numbers, own AS-number and the agreements with your 3 ISP's.
There is no technical problem to do this using ADSL lines except that I would expect that almost all ISP's won't want do it on ADSL lines.
But except that it's a basic BGP4 setup if you want real multihomed access to and from your network.

We use two 7206 as our gateway to the internet and they work without any problem (except 256 MB on one of them has to be upgraded to 512MB before the end of this year because of the big route tables)

/johnny