A. Several options exist that let you force a DC to reregister its DNS records. For example, you can stop and start the netlogon service on a DC to make it reregister all the service DNS records. You can also use the /dsregdns switch with the Nltest command to force a DC to reregister all it's DNS records, as the following sample execution shows:
C:\>nltest /dsregdns Flags: 0 Connection Status = 0 0x0 NERR_Success The command completed successfully
This method lets you avoid losing the netlogon service during the stop and restart.
You can also force reregistration of another DC's records by adding the /server:
C:\>nltest /server:savdaldc02.savilltech.com /dsregdns
I_NetLogonControl failed: Status = 1722 0x6ba RPC_S_SERVER_UNAVAILABLE