> On 9 Apr 2020, at 4.45, Plutocrat <plutoc...@gmail.com> wrote:
>
> On 08/04/2020 19.14, Ben Mulvihill wrote:
>> Thanks for the suggestion. I think my next step will be to investigate
>> imapsync, or maybe isync, which also looks promising.
>
> I've recently migrated a server with imapsync with 150Gb of email and 200+
> accounts. I found the trick with this was the run imapsync in several runs:
> Messages older than 1 year; messages older than 6 months; messages older than
> 1 week, for example. Then just keep running the full sync after that until
> you're ready to switch. If you've just got one email then this should be
> easy. With many addresses, there is a bit of scripting to do first to get it
> all set up.
>
> One gotcha, which I never solved, (mainly due to the fact I had to do the
> whole migration in under a week as an emergency). I could never figure out
> how to get the dovecot indexes correct, so that when the client connected to
> the new server via POP, it didn't re-download all the messages. IMAP was OK
> though.
This is because imapsync does not migrate all data. Such as IMAP UID:s or POP3
UIDL.
Sami
