Windows 2008 server migration to Windows standard 2016. Im having an issue here after a migration to a new 2016 domain controller. The DC holds all the FSMO roles, is the global catalog server, DHCP, DNS points to it and the client desktop do too. yet I want to DCPromo to demote the 2008 server but before I do that I wanted to make sure everything is healthy and working. If I disconnect or power down the 2008 server all the sudden the client stations lose the internal network name and then shows up as "network 3" or 4...etc.. and not the local domain name.
Then I check on the 2016 server and when I go to open AD its giving me errors that no domain controller can be contacted.
At a command prompt I will run the netdom query fsmo and Ill get the error that the domain either does not exist or could not be contacted.
I will run a DCDiag and most tests come back passed except for:
1) Netlogon test - user credentials does not have permission to permission to perform this operation (yet I am sign on at the primary administrator)
2) replication attempt failed between the 2 servers (error 1256)
3) could not open NTDS service on the 2016 server (error x5, access is denied)
4) unable to connect to NETLOGON share - error 6, network name cannot be found (yet this is being shared?)
5) when the 2008 server was down it also showed:
Starting test: LocatorCheck
Warning: DcGetDcName(GC_SERVER_REQUIRED) call failed, error 1355
A Global Catalog Server could not be located - All GC's are down.
Warning: DcGetDcName(TIME_SERVER) call failed, error 1355
A Time Server could not be located.
The server holding the PDC role is down.
Warning: DcGetDcName(GOOD_TIME_SERVER_PREFERRED) call failed, error 1355
A Good Time Server could not be located.
Warning: DcGetDcName(KDC_REQUIRED) call failed, error 1355
A KDC could not be located - All the KDCs are down.
......................... "domain.local" failed test LocatorCheck
when I connect the 2008 server again and run a dcdiag i will get similar errors above except for the last one - but it will still say "All GCs are down"
now the 2008 is no longer a GC but the 2016 server is
Ive been going over this and am not sure what the issue is. DNS and AD seem to replicate just fine when both DCs are running. but i dont want to demote the 2008 server until this is clean
thank you for any help you can provide