When you attempt to start all the domain controllers after a power failure, no domain controller exists to validate users, causing any process that depend on domain authentication to fail on these and others servers.

This behavior occurs because the DNS servers are not yet available on the network.

To workaround this behavior, restart the Netlogon service on each domain controller:

1. Stop the Netlogon service on each domain controller.

2. Flush the DNS cache on each domain controller.

3. Point the domain controller to a correct and live DNS server which is located in the same domain zone as the domain controller.

4. Disable the network adapter.

5. Enable the network adapter.

6. Restart the Netogon service on the domain controller.