We recommend that you do not swap the computer name unless you have a compelling need to do so. Renaming a domain controller has inherent risks. It can adversely affect installed applications and services that have the computer name embedded in their internal settings, and it can prevent Certificate Services from functioning correctly.
Instead, we recommend that you use DFS Namespaces to advertise any public file shares on your network. Use DNS aliases to advertise any as web sites. This removes the need to rename the computer in order to access the network file shares or to access your web sites.
For example, let's assume that your old domain controller is named MyComputer.acme.com and that MyComputer has published a file share named Sales. The traditional UNC path to access the file share is \\MyComputer\Sales. With DFS Namespaces, the file share path becomes \\acme.com\Sales. The latter is an alias for \\MyComputer\Sales.
By using the alias name \\acme.com\Sales instead of the computer name, you can avoid the need to rename the new domain controller after you retire the old one.
Preparation Step: Install and Conigure DNS Namespaces
If your DC publishes file shares (\\MyComputer\xxx), you should install and configure DFS Namespaces as a preparation step. Then change all your client computers to use (for example) \\acme.com\Sales instead of \\MyComputer\Sales.
Alternate Method: NETBIOS and DNS Aliases
An alternate method is to add an alias for the old DC'c name that refers to the new DC. Add the NETBIOS name in the registry of the new DC (OptionalNames). Add the DNS CNAME records in your DNS server. Do this as a post-upgrade step when you retire the old DC.See How to Configure Windows Machine to Allow File Sharing with DNS Alias.
For more information about DFS Namespaces
For more information about DFS Namespaces, see the following: