Sunday, June 17, 2012

File and Print Sharing using DNS Alias (CNAME)

When creating an Alias (CNAME) for a file or print server, some additional steps may be required before it can be used.
Consider the following situation:
We have a File Server called AU_Q_017_951.
We connect to the server from a Windows XP machine, and it works OK using the name of the server.

We create the Alias (CNAME) for the server, as AU_Q_017_951 is not very friendly.  We create the Alias for fileserverQLD.

From Server 2008 machines, this works fine.

From Windows XP Machines, it gives the following error.

(You were not connected because a duplicate name exists on the network.  Go to System in Control Panel to change the computer name and try again.)

Edit the registry on the file server.  Navigate to:
HLKM\system\current control set\services\lanmanserver\parameters
Create a new Dword (32bit) called DisableStrictNameChecking and give it a value of 1.

Reboot the file server.
This should now work for file shares from Windows XP machines.

If the server is 2008 R2, an additional step is required to make printer sharing work via an alias (CNAME)
Without the following, the printer will be visble, but fail to install.
On the print server, run the following command:

reg add HKLM\SYSTEM\CurrentControlSet\Control\Print /v DnsOnWire /t REG_DWORD /d 1

Restart the print spooler to take affect.