Backup DC past tombstone and need help replacing it with another DC with the same name and IP

Question

Hey Everyone
We have a single domain in a forest with 2 DCs with AD integrated DNS configured. The primary DC with all the FSMO roles is a VM (Server 2008 R2) and the backup DC is a physical server (Server 2008 non-R2).
The backup DC's hardware is very old and has been giving us a lot of issues where the system would intermittently BSOD, freeze, black screen only etc. and as a result, the server was turned off for a very long time, definitely beyond the default tombstone
lifetime of either 60 or 180 days.
We want to replace this bad backup DC with another physical server which became available as a spare and is much newer and in a working condition hardware wise. We also wish to ultimately give it the same name (FQDN) and IP to basically make it an outright
replacement for the current bad backup DC.
My questions are:
1.) If we are in a position where the bad server could possibly physically boot and start the operating system and have network connectivity, will we be able to use DCPROMO as one would normally do to demote this DC, or will it have to be done forcefully,
while keeping in mind as I said that the DC is way past the tombstone lifetime period?
2.) If it has to be done forcefully, I am aware that the meta data needs to be cleaned up in AD on the working primary DC, although I have never performed such a process before. If this is done, are there any other things I need to look out for or do
before I attempt to replace it with the other server which I will set up wit the same name (FQDN) and IP, then add to the domain, and then lastly promote as per normal using DCPROMO?
I know we will have to upgrade the scema to 2012RM as the replacement backup DC will be running this newer operating system.
Anything else you wish to add or point out to me would be highly appreciated. Thank you in advance.
Regards,
CTV

Answer 1

Hi,
I would suggest please do the metadata cleanup using the script and then remove object from below DNS console and then run the repadmin /syncall /Aed
https://gallery.technet.microsoft.com/scriptcenter/d31f091f-2642-4ede-9f97-0e1cc4d577f3
Repeat running the vbs script till the wrong/unnecessary dc’s are removed.
         Cross check the removal – dsa.msc [ad users and computers] > Domain Controllers OU
 Adsiedit.msc
 Expand domain partition, select OU=Domain Controllers, make sure only the necessary domain controllers are listed.
 Delete the incorrect domain controllers.
Dnsmgmt.msc [Dns Management]
      Expand the forward lookup zones\_msdcs folder
i.      Make sure only the actual domain controllers are listed, delete wrong Alias recordsremove wrong name server records
ii.      Select the container [forward lookup zones\_msdcs.domain.com\dc\_sites_\sitename\_tcp] > delete incorrect _ldap and _kerberos records are listed.
iii.      Select the container [forward lookup zones\_msdcs.domain.com\dc\_tcp] and delete incorrect _ldap and _kerberos records
iv.      Expand the [forward lookup zones\_msdcs.domain.com\domains\guid\_tcp] and delete incorrect _ldap entries
v.      Select [forward lookup zones\_msdcs.domain.com\gc] – delete incorrect HostA records
vi.      Expand the [forward lookup zones\_msdcs.domain.com\gc\_sites\sitename\_tcp] – delete incorrect _ldap entries
vii.      Select the [forward lookup zones\_msdcs.domain.com\gc\_tcp] – delete incorrect _ldap entries
viii.      Select the [forward lookup zones\_msdcs.domain.com\pdc\_tcp] – delete incorrect _ldap entries
      Expand the forward lookup zones\domain.com folder
i.           
Delete Host(A) records of dc’s which are non-existant.
ii.           
Correct the NameServer (NS) records
iii.           
Follow steps similar to ’ A ii ‘ >> ‘ A viii’
         Dssite.msc [Sites and Services]
      Expand the [Sites\Sitename\Servers] – delete incorrect server’s
B.      Delete incorrect subnet configurations [Sites\Subnets]
      Delete incorrect site links [Sites\IP]