New WAN and internal routing?

[louis0001]

Hi,

we have 50 remote sites all connected into an MPLS network. We have 2 central sites within this MPLS network which are directly connected via a 100mb line via 2 core switches. The only way for clients at any site to reach the internet is via central SITE A which has 2x ASA in standby/failover. Everything goes through here as the ASA's are the gateway of last resort for the network.

Now, we want to add a second internet connection at Central SITE B. Now on the core switch there, it would simply be add the 2x ASA's at this site as the gateway of last resort. So in effect, we have a complete mirror of central SITE A at Central SITE B

My question is...... what would be the implications here? Clients on our network would naturally route to SITE A to get to the internet but now there is 2 ways out of the network. Would they just simply choose which way they wanted to go out via the shortest route?

Louis

[shaps]

Hi 

You can ask the providers to use a routing protocol and use the cost/metric/local preference to alter the route out of your network.   for inbound connectivity if you run bgp you may be able to affect the local provider decision using bgp attributes but you would be best to talk to them about how they handle this.  you will need to be careful of asymmetric routing whereby you go out of one firewall pair and the flow tries to come back into the other firewall pair