Not possible to replicate from 2.3.7 to 2.3.16?

[Jason L Tibbitts III]

[Forgot to send this to the list; sorry.

>>>>> "BG" == Bron Gondwana <brong at fastmail.fm> writes:

BG> No, sorry.

I figured as much; I backed off to 2.3.7 on the new machine so that I
could get a good replica.

BG> Replication across versions is trick at the best of times, and
BG> you're talking about versions 3 and a half years apart!

I had guessed, though perhaps I had hoped that something would simply
tell me that instead of giving odd errors that made me think that I had
misconfigured something.  But I think I have my plan of attack readied.

BG> Unfortunately, your only real option is to upgrade to 2.3.16 on both
BG> at roughly the same time.

Actually my plan is to simply abandon the old, failing master (leaving
it with the current content in case things blow up), upgrade the replica
to 2.3.16, make it the master and set up yet another machine as a
replica.

BG> The upgrade itself should go seamlessly.  Because of the mailbox
BG> format change, you will get an IO hit as each mailbox open causes a
BG> full index file rewrite to upgrade it to the new format!

Not a big deal, though I wonder if there's any way I can force this to
happen all at once in the middle of the night instead of when some user
happens to open their multi-gigabyte inbox.  The new machine is
seriously over-specified for the task at hand so I don't think the extra
IO will be a problem, but it would still be nice to do it all at once.

BG> This also means you can't downgrade again without doing a full
BG> reconstruct of every mailbox.

I hope to not need to do so, but in case I do, that's just
  reconstruct -r
on everything under user, right?  I guess it's a credit to the software
that I've never really have to mess with the recovery tools in the years
I've been using it.

 - J<