Marking a DB server to never be the sync site

[Jeff Blaine]

I am 99% sure that the answer to this is "There is no way.", but I am
going to ask anyway:

Is there any way to mark a particular DB server as never allowed to be
the sync site?

We will have 5 DB servers soon (2 of those at remote sites) and would
very much like the servers at the remote sites to never be allowed to
become the sync site.  Those 2 servers have lower IP addresses than
our "core" 3 DB servers where 80% of all AFS work is done at HQ.

Suggestions?  Comments?