Filed to initialize session with document engine: Unable to resolve Contentdistributor

Error Message in event viewer
Failed to connect to servername.domain.com:13391 Failed to initialize session with document engine: Unable to resolve Contentdistributor.

I got this error log several times. One is from Office Web Apps installation.
I installed FAST for SharePoint before deploying OWA. after that i got this error.
the other one I think it occurs after FAST and SharePoint Server were migrated to a new server using vMotion.

Solution.
Just reinstall FAST Certificate into SharePoint Server again follow the step in the below link.
Configure SSL enabled communication

then restart both FAST and SharePoint server.

Cheers