Does anyone know the step by step to migrate User Profile Service (Social DB) from one farm to another different (the server name is different)? I need to restore all site collection comments
You must move the Managed Metadata service application before you can move the User Profile service application. The reason is your social is associated with the MMS i.e taging notes etc.
you need to follow the same procude as you hvae for the upgrade.
read the below Technet, will guide. http://technet.microsoft.com/en-in/library/jj839719.aspx