DC backup to DC master

I have problems on UCS DC master and I would like to change DC backup to DC master and remove damaged server
How can I do that?

There is a chapter in the standard docs.
3.9. Converting a DC backup to the new DC master

I was notified yesterday that my pointer from two years ago to the docs earned the “hot link” status.
Just to be sure…
The most recent one is http://docs.software-univention.de/manual-4.4.html#domain:backup2master