[Dovecot] Disable imap proxy access

[Ed W]

> How to disable pop3 and imap access during the data migration process
> (duration 5 minutes to 10 minutes). Can i send a custom error message to
> our users ?
>   


I don't recall the exact details, but I think both options are possible 
if you check the dovecot wiki.  There is a good study regarding the 
proxy stuff, and some notes on sending custom errors back (along with a 
note that it's not supported on many clients)

If you use SQL then you could simply change the query temporarily

Also when I do my migration I change the permissions on the home folders 
first (root:root say) - this way if I muck something up they don't get 
logged into the old mailbox.  Then I reset the permissions back on the 
new server and update the proxy settings.  This also gives a random 
error back to the client in the meantime if they try and log in.

I should think that the above could even be scripted and run per mailbox 
for a very subtle downtime period... I use rsync once while the mailbox 
is online, then change perms so that the user can't login, then do a 
final rsync to get any changes across.  I didn't check whether there is 
a problem with an existing connection still accessing the data after the 
perms were changed though...

Good luck

Ed W