Why is there a "no" DNS server available "error while installing DNS and working properly?

When NetlogonWhen the service cannot register or cancel registering multiple resource records, the System Event Log will recordNetlogon5781Error message. The event description does not contain the names of these resource records. In addition, the event description may be "no ",DNS servers are available ",

note: the common cause of these errors is that the domain controller references itself as the DNS server in its TCP/IP attribute. When the domain controller starts with this configuration, the netlogon service may start before the DNS service starts. Because the netlogon service must register records in DNS , and the DNS service is not available, an error may occur. In this case, you can safely ignore these errors, because the netlogon service will attempt to register these records again in about 5 minutes, the registration will be successful. However, in this case, there are two ways to avoid these errors:
make sure that the domain controller does not reference itself as the DNS server in its TCP/IP attribute.
Configure the netlogon service to depend on the DNS service. This causes the netlogon service to start after the DNS service is started. To do this, run regedt32 and go to:
HKEY_LOCAL_MACHINE/system/CurrentControlSet/services/netlogon
In the right pane, double-click the dependonservice value, and then add DNS to the next available blank line. Click OK to exit the Registry Editor.
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