Dual WAN Cisco 1811

[argnetworking]

Hello,

I have a Cisco 1811 with  a dual wan and I would like to know if it is posible to do load balance and failover with two internet connections.

The examples I found where all about doing just failover with two connections, I could't found a configuration to do load balance.

Does anybody have an example configuration? I have two internet connecitons with static IP.

Thanks a lot.

Gonzalo

[Federico Coto Fajardo]

Hi,

You can load balance the outbound traffic between both internet connections if setting both default gateways:

ip route 0.0.0.0 0.0.0.0 First_ISP

ip route 0.0.0.0 0.0.0.0 Second_ISP

If both routes above have the same metric (1), traffic will be load balanced, if both metrics are different, the router will use the smallest metric and use the other one as backup (failover).

I guess you can ask your ISP about BGP as well in case you want to control traffic via both connections (it depends if using a single or two ISPs).

Federico.

[k.hariharan1 · Accepted solution]

it depends,

1. if you got both the links (if its a serial delivery) from same isp you can configure MULTILLINK .

2. if you got two links from two different service provider , then each isp might have given you thier ip block so in this case if you are just configuring static routes pointing to two isp will not work. you need to configure IOS NAT LOADBALANCING means your local ip should be nated with two different isp ip address  in your router . also in this case onle per destination load sharing will work and  per packet load sharing will not work with IOS NAT LOAD BALANCING.

Hope this helps

Regards,

Hariharan k