Step to perform Database Portability:
I have worked with many customer where they are concern about the exact steps of Database Portability feature.
I have tested below solution in my lab and it was 100% successful. Please find below steps for database portability to restore a database on another server.
We will dismount database1 on MBX1 server and will restore it on MBX2 server with help of Exchange 2010 database Portability feature.
Set-MailboxDatabase Database2 -AllowFileRestore:$true
Get-mailbox –Database database1 | Set-Mailbox –Database database2
Restoring back to the old server:
Note: Have to copy the latest database file while performing it to avoid any data loss or have to perform this after taking full backup.