> doc/install-upgrade.html
This information assumes you are upgrading on one box. My situation (and I suspect it is the situation of most production systems) is having 2.1 set up clean (i.e. no mail or metadata) on a second machine, and now I want to get all the mail from my 2.0 machine to it, without upgrading the 2.0 machine. This insures that falling back to the old server is trivial, in case the upgrade fails. The documentation doesn't discuss at all how to transfer mailstores between machines. I think this is what Patrick and I both want to know.
