Hi Noel, Great answer! Thank you very much, Ronan
2010/8/19 Noel Jones <njo...@megan.vbhcs.org> > On 8/19/2010 2:58 PM, Ronan Lucio wrote: > >> Hi All, >> >> I need to re-install a new mail server. >> So I have the actual server running on and ordered a new one >> where I'm installing and configuring newer softwares. >> >> It's done and I need to move all domains and it's accounts to >> the newer server. >> Once there are so many gigabytes to move, I'll need to move >> domain-by-domain, the will take weeks to move it all. >> >> My problem is the DNS propagation. >> Our server are configure with a 2 hours TTL >> >> So after I move a domain and it's accounts, the next 2 hours >> both servers (old one and new one) will receive messages (due >> to DNS time propagation). >> >> What I want to is configure the old server to relay mails sent >> to that moved domain, to the new server. >> How can I do that? >> > > > Easy way: > Rather than forwarding mail, defer all mail for the moved domain. When the > sender retries, they will eventually get the new server. This may delay > some deliveries during the migration, but few people will notice. You can > minimize the delays by changing your DNS TTL to a shorter value; 10~30 > minutes is probably a good compromise. > > This example config assumes the default smtpd_delay_reject=yes. We do this > in smtpd_sender_restrictions so that a mistake doesn't make you an open > relay. > # main.cf > smtpd_sender_restrictions = > check_recipient_access hash:/etc/postfix/moved_domains > ... any exiting checks go below here ... > > > # moved domains > example.com DEFER server maintenance > example.org DEFER server maintenance > > > > Hard way: > When postfix accepts mail for a domain but final delivery is on a different > server, it's called a relay domain. > The domain name must be added to the relay_domains parameter, and valid > recipients must be listed in relay_recipient_maps. > It's important that the domain name is removed from all other *_domains > parameters so the domain doesn't belong to multiple address classes. > http://www.postfix.org/ADDRESS_CLASS_README.html > > If postfix can't find the new MX for the domain using a normal DNS lookup, > add a transport_maps entry pointing to the correct server. > # main.cf > transport_maps = hash:/etc/postfix/transport > > # transport > example.com relay:[10.1.10.100] > > http://www.postfix.org/postconf.5.html#transport_maps > http://www.postfix.org/transport.5.html > > > > -- Noel Jones >
