Server migration

[Gandalf Corvotempesta]

2016-10-24 11:23 GMT+02:00 Karol Augustin <karol at augustin.pl>:
> When I am doing this I just turn off both servers for the third sync.
> Its short enough to not cause much problem. And then after third sync I
> start the new server and all clients can connect to it so I also
> mitigate any problems resulting from clients that would be still
> connected to the old server. The last issue depends on the way you force
> everyone to use new server (DNS, routing, etc).

The speed for third sync depends on the number of files to be scanned.
I have mailboxes with tons of very small emails, thus even if the first two sync
has transferred all datas, the scan made by rsync to check which files
needs to be transferred
requires many hours.

My own mailbox has 80GB of mails. I can sync everything on a new
server and then start
a new rsync phase. this new phase requires exactly 1 hours and 49
minutes (as I can see from
the last night backup). Transferred data: 78MB. 1 hours and 49 minutes
to transfer only 78MB.

> Remember that beside the new emails that could arrive during sync you
> have also all sorts of user-generated operations as move, delete etc. So
> if you just do 3rd rsync without --delete you can end up duplicating
> users' emails if they move them during procedure.

By shutting down both servers, the "--delete" argument could be used
with no issues.