Multiple MTAs during migration

[bmcdonald]

I've just installed Zimbra 4.5.7 under Ubuntu 6.06. Our company is migrating from sendmail running on FC3. Here's the dilema. I have two MX records:

example.com. MX 10 mail1.example.com.
example.com. MX 10 mail2.example.com.

mail1 is the sendmail system, mail2 is the shiny new Zimbra system.

We're planning a phased migration and during that time, we will have users on both systems under the same domain. Both mail1 and mail2 need to be aware of all of the users of example.com regardless of whether their mailbox resides on mail1 or mail2 so that delivery of messages (from local or remote sources) should be possible for any user in the example.com domain.

What do I need to configure on these two servers to make them aware of each other in domain example.com?

Regards,

Bob

[mmorse]

Welcome to the forums,

This is what you need: Split Domain - Zimbra :: Wiki
-First choose a primary or secondary config

[support.txdistlcms.org]

Thanks - I think that will take care of my issue also.

The pdf docs need an update I think - they state that routing is only done by DNS. I tried having the new zimbra server receiving mail for zimbra.domain.com in DNS and the old server forwarding the accounts individually as I migrated each user. DNS for domain.com points still to the old server. Users can receive mail fine, and can email outside the office and other migrated users. However, if the zimbra user tries to email a user that has not been migrated zimbra (postfix) would fail without trying to send to the old server.

[support.txdistlcms.org]

I am planning, from the docs:
-----------
1. The secondary system needs to accept mail for accounts that are hosted on the secondary, but must forward all other mail for accounts on this domain to the primary system.

On a zimbra server, you can accomplish this piece of mail routing with these commands:

$ zmprov md example.com zimbraMailCatchAllAddress @example.com
$ zmprov md example.com zimbraMailCatchAllForwardingAddress @example.com
$ zmprov md example.com zimbraMailTransport smtp:mail.example.com
-----------

How do I remove this routing once my migration is complete and I want to get rid of the mail.example.com server?

[mmorse]

zmprov md domain.com zimbraMailCatchAllAddress ""
zmprov md domain.com zimbraMailCatchAllForwardingAddress ""
zmprov md domain.com zimbraMailTransport lmtp:server.domain.com:7025

(you might need to use single ticks instead of double)

If you continued on in that article, it goes:

2. We also highly recommend that, in a secondary Zimbra system, you turn off DNS lookups and internet wide message routing from the secondary host and route all mail through the primary. You can accomplish this by:
$ zmprov mcf zimbraMtaRelayHost mail.example.com
$ zmprov mcf zimbraMtaDnsLookupsEnabled FALSE

so of course you will need to change those back as well if you modified them