Hi
I was on vacation and my collogue changed something in Doamin controller servers

Actually we have 3 DCs in our environment. After I came back I found failures in the DNS and in DC.
Server1 was primary and Server2&3 was Backup
Now Server2 becomes Primary and the other are backup

Many clients in the environment appear as Comp.192.2.2.1 (where comp is the client name and 192.2.2.1 is the IP address of server1)
But before they were appearing as Comp.company.net

after checking their event viewer I found this error
"Attempt to update DNS Host Name of the computer object in Active Directory failed. The updated value was 'mas.192.2.2.1'. The following error occurred:
The parameter is incorrec

What shall I do
Can you help please?

This behavior can occur if the DNS domain name for the computer does not match the Active Directory domain name. Specifically, the Change primary DNS suffix when domain membership changes check box has been cleared, and contains a DNS domain different from the Active Directory domain of which the computer is a member. To view this check box, right-click My Computer, click Properties, and then click the Network Identification tab.

If the disjoint namespace is unintended, click to select the Change primary DNS suffix when domain membership changes check box and reboot the computer.

If the disjoint namespace is intended, make sure that the Change primary DNS suffix when domain membership changes check box is not selected, and then follow these steps:

1. Start the Active Directory Users and Computers snap-in.
2. In the console tree, right-click Active Directory Users and Computers, and then click Connect To Domain.
3. In the Domain box, type the domain name, or click Browse to find the domain in which you want to enable computers to use different DNS names, and then click OK.
4. Right-click Active Directory Users and Computers, point to View, and then click Advanced Features.
5. Right-click the name of the domain, and then click Properties.
6. On the Security tab, click Add, click the Self group, click Add, and then click OK.
7. Click Advanced, click Self, and then click Edit on the View menu.
8. On the Object tab, in the Apply onto box, click Computer Objects. Under Permissions, click Validated write to DNS host name, and then click the Allow check box. Also, you may have to click Validated write to service principal name, and then click the Allow check box.

Hi and thank you for your answer

I moved the Operation Masters to the first server and it seems that it is okay

But there are some problems in connection between the DNS and Active Directory.

All clients are registered in Active Directory but some of them are not registered in the DNS record

I checked one of these clients tried to register the client in the DNS by using this command ipconfig \ registerdns and found in the event viewer this error

The system failed to register network adapter with settings:

Adapter Name : {BFCFFA4A-0DA3-407B-BF20-53FDE848C592}
Host Name : mas
Adapter-specific Domain Suffix : 172.161.106.182
DNS server list :
172.161.106.181
Sent update to server : None
IP Address(es) :
172.161.106.197

The cause of this DNS registration failure was because of DNS server failure. This may be due to a zone transfer that has locked the DNS server for the applicable zone that your computer needs to register itself with.

(The applicable zone should typically correspond to the Adapter-specific Domain Suffix that was indicated above.) You can manually retry registration of the network adapter and its settings by typing "ipconfig /registerdns" at the command prompt. If problems still persist, contact your network systems administrator to verify network conditions

Please if any one got this problem before can help

You can go into the DNS console and manually add the machines.