[c-nsp] cisco-nsp Digest, Vol 76, Issue 117

[gokhan senol]

Hi 
I need a help about designing the topology below.
 
the customer has HQ and now wanna design disaster center. As you can guess both HQ and Disaster side have server farms. (Actv.Dir. - Exc. - some applıcation servers)
also there are  about 50 remote sides. its an mpls topology.
 
case  : if  HQ connection to ISP goes down then the server farm in HQ will be unreachable and the remote sides will access to disaster side. its ok
but if only one server goes down in HQ , what kind of config should I do on the HQ router so the connections come to that server will be rerouted to the backup server in disaster side. 
 
and also I thougt giving same ip subnet for HQ and disaster and also I thought using overlapping nat to access both side to eachtoher.  Is it correct design ?
 
thnkx evry1