Why did DNS break after promoting a domain controller?
Promoting a backup domain controller to primary causes all DNS entries to disappear on the PDC, resulting in a complete failure of name resolution. Network traffic mysteriously fails to hit the second DNS server during this transition, leaving administrators confused.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Manually changing the DNS server order on specific machines, workstations, and the firewall.
- 2Checking DHCP scopes and static addresses to ensure no clients point to the server
- 3Running health checks and dcdiag
- 4Forcefully removing the server and cleaning up metadata
In their words
Unedited, most upvoted first, each linked to the thread it came from.
Where this came up
People with this problem also raised
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