Forum Discussion
Confusion on adding a secondary domain controller.
Yes, you'll need to stand up a second instance of windows server, patch it fully, join existing domain, add active directory domain services, then the last step would be to check the notification area for 'Promote this server...…….." (this of course is a ten thousand foot view of process) You could also follow along here.
I still don't fully understand how this works but I will install Windows Server on a second Virtual Machine, install and set up Active Directory and then join it to the "existing domain". I think the idea here is to have two separate Active Directory installations running joined to the same domain, so one is a backup. Does that sound about right?
Windows active directory provides for a multi-master model. One would always want to have at least two domain controllers for high availability and disaster mitigation.
https://support.microsoft.com/en-gb/help/197132/active-directory-fsmo-roles-in-windows
