Just wondering what the best practice is here. I have two sites, one is in Dublin and the second is in London. Dublin has an IP range of 192.168.7.0 and London is 192.168.8.0. I have a forest/Child setup e.g. Forest is company.com and then the children are dublin.company.com and london.company.com. I wanted to have a DC for the company.com domain in each site (for DR purposes) but I'm not sure how that will work in Sites/Services having two DCs for the same domain being associated with a different subnet. Plus I will be installing Exchange 2010 in both Dublin and London.