This is in reference to the original question here (please read this first!):
OK, seems to be a bit of a problem that has come up:
Since we do not have the new branch open yet, we have simulated a default gateway for the new 192.168.2.X network using our firewall to redirect traffic. I have put the new DC on the .2.X network with the simulated gateway address and such on it. With all that, it seems I am able to communicate with the old DC, but cannot browse to any other computer on our 192.168.1.X network (also, from my workstation on the 192.168.1.X network I am able to successfully browse to the new DC on the 192.168.2.X network and see it's shares, but the new DC cannot browse to my machine and see my shares). Furthermore, it seems that replication between DC's is one-way at this point - the new DC has successfully replicated info from the old DC, but the old DC seems to not be picking up any changes to AD (for example, Sites and Services) from the new DC. So the new DC seems to be able to pick up the changes from the old DC, but not the other way around.
A big example of this, as mentioned above, is in AD Sites and Services. On the new DC, I had created the new site, the new subnet, and moved the new DC server object to the new site. There is a site link between the sites, and everything seems to be setup correctly there. However, I just noticed today that the old DC reflects none of those changes in AD Sites and Services. Hence, it seems to not be pull-replicating correctly with the new DC.
Am I missing something here? Let me know if I can provide any other information.