Since Server 2 appears to be the target environment, copy Server 2’s actionsite.afxm or masthead.afxm file to the /var/opt/BESServer/wwwrootbes/Uploads folder on Server 2. For convenience, this file should be named masthead.afxm.
From the Server 1 BigFix Console, take action on the Task 1516: Switch BES Client Masthead - BES >= 9.0, found in the BES Support Site.
In the Take Action dialog box, choose the appropriate target clients. Then open the Action Script tab, and modify the URL in line 1 of the Action Script to point to Server 2. (something like: http://server2:52311/Uploads/masthead.afxm ).
After the computers show up in the new environment, you can upgrade the BigFix Clients to 188.8.131.52.