Forgot password to local administrator on server. If it possible to reset from domain

Yes. Domain admins have Local Administrator privileges and can reset passwords on all local user accounts.

Use the "net user" command to reset the password/enable the account on the machine for which you have forgotten the local admin password.

Or just open the Local Users and Groups MMC and change the password there.

Here you go:  See the bottom for 2012 specifics.

Resetting Administrator Password in Windows 2008 R2/ 2012 R2

· Boot from the Microsoft Windows Server 2008 DVD
· From the Install Windows menu, click “Next”.
· Select “Repair your computer”
· In the System Recovery Options, select the Operating System instance that you wish to repair and click “Next”.
· Select “Command Prompt”. The
· At the command prompt, run the following commands:
c:
cd windows\system32c:
ren Utilman.exe Utilman.exe.old
copy cmd.exe Utilman.exe
· Reboot the server allowing Windows to load as normal
· At the logon screen, press Windows Key + U.
· As the command prompt, enter the following command:
net user administrator Password12
This will set the password for the Administrator user to be Password12 (case sensitive).
Closing the command prompt, you should now be able to log back onto the server using the password you have provided in the last step.
Cleanup Steps
Once you have verified you can log on to the server you will have repeat the steps above and boot using the Windows Server 2008 DVD/ISO and run the command prompt again.
· Delete the newly created Utilman.exe from C:\Windows\System32
· Rename Utilman.exe.old back to Utilman.exe
You should be back up and running as if nothing ever happened.

2012 R2 Specifics
· After choosing "Repair your computer" you are asked to choose and option….click on "Troubleshoot" then choose "Command Prompt".

Did net user commend but only listed the domain user not the local [I changed the password on that user, it changed the password of the domain login not of the local)

Would you give me little more guidance where in the console I will find this option.

PS there is a work around way doing it via GPO. But prefer doing it correct way.

The way doing  it thru the installation dvd and cmd is only used a last option

Right click the start button, select Manage Computer, from there, you can get to the Local Users and Groups portion of the computer management console. The users listed there are the local users on the server. Change the password for the local administrator there.

See attached snapshots from MMC and computer management there is no such option.
Computer-management.JPG
MMC.JPG

As Adam said..it's a DC.  When you did my suggestion, you changed the password you needed to.