Restoring a Domain Controller - When other DC's are available

Question

I'm trying to get some clarity and confidence on the proper way to restore domain controllers.  here are my questions:
1. What is the proper way to restore a Domain controller into an existing Forrest where other domain controllers are present when you have a system state backup taken by Windows Server Backup?
1a. In this scenario - will i need to enter into DSRM mode prior to booting the server?
2. What is the proper way to restore a Virtualized Domain Controller into an existing Forrest where other domain controllers are present when you have a 3rd party image based backup solution that has HyperV VSS writers?  
2a. In this scenario - will i need to enter into DSRM mode prior to booting the server?

Answer 1

1. What is the proper way to restore a Domain controller into an existing Forrest where other domain
controllers are present when you have a system state backup taken by Windows Server Backup?
You can restore the DC using two possible methods:
Method 1: Do a non-authoritative restore using a system state backup. Do not do an authoritative restore so that you do not lose recent changes here.
Method 2: If the DC is an FSMO holder then size the FSMO roles to another DC, do a metadata cleanup and then re-install the server and promote it again as a DC. If it is not an FSMO holder then simply do a metadata cleanup and then re-install
the server and promote it again as a DC.
1a. In this scenario - will i need to enter into DSRM mode prior to booting the server?
Yes. You need to get inside DSRM mode to restore the DC from a system state backup.
2. What is the proper way to restore a Virtualized Domain Controller into an existing Forrest where
other domain controllers are present when you have a 3rd party image based backup solution that has HyperV VSS writers? 
You can read that: http://technet.microsoft.com/en-us/library/d2cae85b-41ac-497f-8cd1-5fbaa6740ffe(v=ws.10)#backup_and_restore_considerations_for_virtualized_domain_controllers
Also, see that about DC cloning in Windows Server 2012 and higher: http://blogs.technet.com/b/askpfeplat/archive/2012/10/01/virtual-domain-controller-cloning-in-windows-server-2012.aspx
2a. In this scenario - will i need to enter into DSRM mode prior to booting the server?
You can find the details in the links I shared.
This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.
Get Active Directory User Last Logon
Create an Active Directory test domain similar to the production one
Management of test accounts in an Active Directory production domain - Part I
Management of test accounts in an Active Directory production domain - Part II
Management of test accounts in an Active Directory production domain - Part III
Reset Active Directory user password