What is the importance of the “gc._msdcs.<mycompany>.com” A records?
Environment:
1) Split DNS – Unix Bind and AD integrated DNS
2) DCs use:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters]
"RegisterDnsARecords"=dword:00000000
to avoid registering the A domain record on our Unix DNS server, which will not accept them. This record is put in manually. This registry entry also prevents these failures to register from being written into the system event log.
3) Today my DNS admin noticed that the “gc._msdcs.<mycompany>.com” zone was not populated correctly, with hardly any of the current GCs listed. Some of the IPs that were listed haven’t been used for years. The GC A record for our current GCs obviously is not written because of #2.
4) If I check for enterprise GCs using a tool like replmon, all of the GCs show up.
5) There are no AD issues that we are aware of.
So the question is – what are these A records used for, if anything. It would appear in our scenario this zone is unused.
Any thoughts/comments are appreciated!
TIA!
Mike Thommes
