Quoting "Gary Chodos" <gcho...@gmail.com>:
On Fri, Aug 14, 2009 at 5:17 PM, Sahil Tandon<sa...@tandon.net> wrote:
On Fri, 14 Aug 2009, Timo Sirainen wrote:
On Aug 14, 2009, at 12:36 AM, Gary Chodos wrote:
We have to replace one mail store (foo.example.org) with another
(bar.example.org). I rsync'd the maildirs from foo to bar today and
the plan is to hold all delivery (in the SMTP server) on foo over the
weekend, rsync again (this time it should be much faster since the
large xfer already occurred today), then flush the SMTP queue on foo
towards bar, direct all new deliveries to bar.example.org. Users
currently access their IMAP mailboxes via imap.example.org. I plan to
just 'flip the switch' at DNS so imap.example.org points to
bar.example.org (instead of foo.example.org) so users don't have to
change anything on their end and should not even notice this change.
And I guess you also thought about the DNS cache TTLs?
The OP should also consider killing dovecot during the rsync
(similar to what
another member of this list suggested). Then restart with a new
configuration that proxies incoming IMAP connections towards the new server
in case some clients still hit the old server before full DNS propagation.
To make the proxy feature work I had to allow plaintext auth on 143
from old -> new server. I use firewall rules to prohibit anyone
except the old server from accessing the new one on port 143. Does
this pose a security issue? Is there something else I should do to
prevent security holes?
I wasn't really paying attn to this thread, but I just did this. I
used ZFS snapshots this time, last time I used rsync. Both my boxes
were behind load balancers, so it was a simple IP change there and
seemless for the end-users. I also upgraded to Dovecot 1.2.
No so seamless was - For some reason, users who use AVG email scanning
with Outlook are no longer able to POP mail. The download 'freezes'.
I redirected POP from Dovecot to qmail-pop3d, had users change the
fqdn of the mail server, I wiped out existing mailboxes, I had users
try to add brand new mailboxes, I changed the pop3_uidl_format - but
nothing worked. The only solution was to disable AVGs email scanning.
Just a heads up - something is amiss.
Rick
