I'm an IT guy at a start-up retail chain which uses AD (I've managed AD before but it was inside one physical location). Right now each site (HQ, shop1, shop2 and shop3) uses it's own AD domain. I'm looking to merge those into one so that the user accounts are shared and I don't have to recreate group policies manually.
All users, computers and printers are inside a special OU in each domain. For example the domain for shop 1 is shop1.example.com and all computers and users are inside shop1 OU. This was done specially in preparation for the future merging.
So my plan was to use hamachi to link the domain controllers. The reason behind this is that the company doesn't want to spend money on hardware-based vpn solutions and some sites have very poor internet connection that I would prefer to keep as much as possible inside the physical networks.
Is this possible? If yes I how would I go about with the merger (got no clue about multiple DCs, replication, AD's sites, etc)? Also, what sort of problems can I expect to run into with this setup (I'm using DCs also as print, DNS (obviously) and file servers)?