How to reinstall 2012 server (with active 2003 member server)

I have a domain with an 03 server and 2012 (r2 I think) server.  The 2012 box is GC and has all the roles, but the 2k3 server is still a member of the domain etc - the domain function level is obv 2003.  Glad the 03 box wasn't decommissioned yet as the 2012 box got hit with ransomware.  Unfortunately their usb backup drive was also encrypted and they had no offsite setup.  I need to reload the OS as I can't get SQL running again - cant uninstall it, cant install it, cant repair...its all kind of jacked.  Whats the best process to get it reloaded and back as the GC of the domain? Do I need to assign the roles to the 03 box first, then dcpromo, then reinstall OS and probably with a different name then before for good measure?
Thanks
LVL 1
rhwimmersAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

bbaoIT ConsultantCommented:
i think you already know the right approach and have given the main steps.

my two cents to contribute would be:

1. double check all references from clients and severs to the existing 2012 server. remove or disconnect them before physically remove the server from the network.

2. double check all resources accessible from the 2012 server to make sure there's no executable ransomware remaining on the network.

3. once the new 2012 server has been installed from the scratch using genuine media (read only preferred), never run any old application or executable from the backup of previous 2012 server.
rhwimmersAuthor Commented:
So I DO need to transfer fsmo roles to 03 server or when I dcpromo will it know to give them to the 03 server thats on the domain?
bbaoIT ConsultantCommented:
yes, it is automatic in normal situation.

you situation is a bit complicated: first it is a 2012 server to be removed from a 2003 domain, second is the 2012 sever was hit by ransomware. i would at least double check if the FSMO role has been successfully transferred after the depromotion.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Lee W, MVPTechnology and Business Process AdvisorCommented:
Your title:
How to reinstall 2012 server (with active 2003 member server)

I have a domain with an 03 server and 2012 (r2 I think) server.  The 2012 box is GC and has all the roles, but the 2k3 server is still a member of the domain etc - the domain function level is obv 2003.  

So you misunderstand.  The domain functional level has NOTHING TO DO with member servers  Domain and Forest functional levels ONLY apply to DCs.  If the 2003 is a member server and not a DC (this is where terminology is IMPORTANT!!!) then your domain functional level could well be 2012 if that was the only DC!

Glad the 03 box wasn't decommissioned yet as the 2012 box got hit with ransomware.  Unfortunately their usb backup drive was also encrypted and they had no offsite setup.  I need to reload the OS as I can't get SQL running again - cant uninstall it, cant install it, cant repair...its all kind of jacked.  
Whoa - SQL?  Your subject doesn't mention SQL and it's not clear where it was running. On the DC?  On the 2003 box?  On a third unnamed system?  What?!  Depending on where it is and what it was (and whether or not it's data was encrypted) You COULD potentially shutdown the services, copy the MDF and LDF files to a new SQL server, attach them, and go from there.

Whats the best process to get it reloaded and back as the GC of the domain? Do I need to assign the roles to the 03 box first, then dcpromo, then reinstall OS and probably with a different name then before for good measure?
What I'd probably do is setup a new VM (this should be ALL VIRTUALIZED - makes backups and replication (for off site DR and backups) potentially easier AND if gives you another license for server 2012 (R2).  One 2012 server license grants you TWO VMs (with one physical install as it's host ONLY - no other services AT ALL).
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Ransomware

From novice to tech pro — start learning today.