Autodesk recommends that every Vault upgrade start with a validated backup.

Review these essential steps for a successful migration:
Create a backup first. Use the Back Up and Restore Wizard to create a full backup. For detailed steps, see Back Up or Restore a Vault.
Test the migration. Run the upgrade on a test system first. This helps you estimate the time needed and find potential issues.
Plan for rollback. Have a plan ready to restore your backup if problems occur.
Zip backup folders. When you move a Vault Backup folder, always zip it first to avoid data corruption.
Use a test system. Install the new version on a test server and restore your backup there before touching production.
The following procedure for testing the upgrade is the preferred method for validating a backup.

Perform a test upgrade of the Vault server on a machine similar to your production server. A test upgrade confirms that your backup is valid. It also reveals potential issues without affecting production.
The table below shows the benefits of matching your test environment to production:
If you cannot create a test environment similar to production, use virtual machines. VMWare or Microsoft Virtual PC are low-cost options. Virtual machines lack many benefits listed above. However, they are far better than skipping backup and migration testing.
Use the Vault server application to restore the production backup in the test environment.
If the migration stops because of a timeout error, follow these steps to resolve it.
First, look in the ADMS log file to find the cause:
C:\ProgramData\Autodesk\VaultServer\Filestore\ADMSConsoleLog-YYYYMMDD.txt
Search the log file from the bottom up for "timeout." If you find a timeout error with a time stamp that matches when the migration stopped, follow these steps:
On the Vault server, open Windows Explorer. Navigate to C:\Program Files\Autodesk\ADMS Product 20__\Server\Web\Services.
Create a backup copy of the Web.config file.
Open the Web.config file with Notepad. Look for this line:
Double the existing values for defaultcommand and longcommand.
Save the Web.config file.
Open the ADMS console.
Do one of the following:
If a yellow warning symbol appears next to a Vault, right-click the vault and select Migrate.
If no yellow symbol appears, close the ADMS console. Then perform a build-to-build migration:
Open a command prompt. Navigate to the installed location of Connectivity.ADMSConsole.exe.
Run the ADMS b2bmigrate operation in command line mode:
Example: Connectivity.ADMSConsole.Exe -Ob2bmigrate -VUadministrator -VPadmin_password -DBUsql_user -DBPsql_password
Replace admin_password with the administrator password for the -VP switch.
The last two parameters, –DBU and –DBP, are only required if the sa password is not the default.
Verify that the filestore and databases are complete. Confirm that the restored environment works correctly. Use a client to verify the content. Use the Vault server application to verify the configuration.
Apply the processes in this document to the test environment. Testing provides a safe way to experience the migration process. You can discover unexpected issues without affecting production. Although testing takes time, it saves time and stress in the long run.