Authorization of Windows Server 2008 accounts. How does incorrect DNS server configuration affect user authorization in AD?

Question

Domain Name System

Configured at the small enterprise AD, DNS, DHCP. Everything worked on the client side, turned everything off, I come in a week, client computers are not authorized through different accounts ("The specified domain does not exist or it is impossible to connect to it"). IPs arrive correct, the server responds.

Answer 1

turned everything off

Including servers?
Do not turn off the domain controller.
And if you do, make sure that at least one of his replicas continues to work.
There shouldn't be much difference between the time on the computers and the time on the AD controller. If it is, the computers will lose their connection to AD.
Users must use the same DNS server that your AD is integrated with as their DNS server.
For a domain controller, if the DNS role is deployed on it, 127.0.0.1 must be specified as the DNS server.
A few more best practices for deploying DNS in an AD infrastructure:
https://blogs.technet.microsoft.com/askds/2010/07/...
https://blogs.technet.microsoft.com/askds/2010/08/ ...
https://technet.microsoft.com/en-us/library/dd3918...
Sometimes the cause of an AD connection error can be seen in the Event Log on the computer or on the controller itself.
You can look at the status of AD using dcdiagfor errors.

Answer 2

A properly configured DNS is required for AD because all AD services, including domain controllers, are looked up through DNS queries.

Answer 3

Most likely out of sync in time. Not enough time has elapsed to "rot out". The exact error in the studio.
Correct DNS operation is a prerequisite for using AD.