DC Health Check
The following is a quick outline of the commands you can use to query and verify the health of a domain controller and its associated domains.
dcdiag
dcdiag is a command-line tool that helps provide insight into the health of a domain controller and assist with identifying issues.
The following command(s) will query and validate the health of the domain controller.
# performed a basic test of the domain controller
dcdiag /v
# performs a comprehensive test of the domain controller
dcdiag /v /c
# performs a comprehensive test including verifying all DNS settings
dcdiag /v /c /d
/q will output only error messages.
/a will test all DCs within this "site."
/e will test all DCs within the "enterprise."repadmin
repadmin.exe is a utility to help administrators diagnose Active Directory replication issues between domain controllers.
The following command will identify if any domain controllers are failing inbound or outbound replication.
PS C:\Windows\system32> repadmin /replsummary
Replication Summary Start Time: 2022-01-26 20:57:54
Beginning data collection for replication summary, this may take awhile:
......
Source DSA largest delta fails/total %% error
DC1 58m:00s 0 / 10 0
DC2 58m:26s 0 / 10 0
Destination DSA largest delta fails/total %% error
DC1 58m:27s 0 / 10 0
DC2 58m:01s 0 / 10 0