Just a quick note on how you can force AD DS replication. You can do this issuing the following command:
Repadmin /syncall DC_NAME /APed
To decipher parameters: /A(ll partitions) P(ush) e(nterprise, cross sites) d(istinguished names). Essentially with this command you can do the same as Replmon used to do in Windows 2003 but in in one step. Don’t forget to replace DC_NAME with name of one of your domain controllers. Of course there are other methods to do that, including using Active Directory Sites and Services console (dssite.msc) like that (from/to selected DC):
Or like that:
When to use? When you made some changes in AD DS partitions and don’t want to wait or when you want to have a quick test of AD DS replication.