I have a customer that has setup their AD Site design based on the domain structure as opposed to the actual physical network structure (although they have subnets defined based on domain as well). Initially, they were all in one building. So I have 5 sites that are all added to the defaultsitelink and based on the 5 domains. They want to maintain this structure if possible.
Now, however, they actually have a new field office for failover that needs to have a DC for each domain in that office. My initial thought is I create a new site representing the field office (with a new subnet) and create a new site link. In the Site link, I would add the field office site and all of the other sites that are based on the domain. In the end I would have the original default site link with all the sites in it other than the field office, as well as the new site link with the field office and the other domain sites in it. This way I could manipulate the replication costs for the field office if I needed to.
Would this work and are there any issues that could occur?