We currently host our own domain controller (small company) locally on dedicated h/w. However to mitigate disaster we're considering the use of virtualisation and cloud hosting.
One thought is
Virtual primary domain controller hosted in the cloud + a local (secondary) virtualised server running in the office as a cache?
Is this possible or should I consider something else? We're happy to pay for the decent hosting and DR but this is really out of my experience.
If security isn't a huge concern, I would recommend using Amazon's EC2 instance. If bandwidth is an issue, you could very easily use the /async switch for replication. Joe Field has an excellent article on how to host Windows Domain in the Cloud
In theory you could configure Samba as a domain controller under GNU/Linux. With the advantage being that there are many cheap GNU/Linux Virtual Private Server (VPS) providers.
This topic interests me since I am looking to do the same thing for a windows network at a small office. I'll post back here if I find anything of interest.
You can do it by using truestack direct connect- migrate the domain, remove the on-prem server and connect the clients directly to Windows domain in AWS.