[Mailman-Users] Migration to a new server: recommendations for testing the new Mailman server before changing DNS records; also how to avoid lost/bounced messages during change-over?

[David]

I am beginning to wonder if it is even possible to test Mailman before
going live. With opendkim, the TrustedHosts file reflects the IP address
and domain name the server will have after it is live (after I swap IP
addresses).

Therefore, opendkim won't work now. And if I go fiddling with config files
for testing (and changing to a temporary IP address, for example), then I
increase the risk that the server won't work after I swap IP addresses and
go live.

It seems to be a bit of a dilemma...