Testing Zimbra with same domain as production email server.

[millerdc]

I would like to test a zimbra server using the same domain as my current production email system and maybe eventually migrate all my users to it over time. I have an "Idea" but I don't know for sure if it will work or if there is a better way.

The mx for my domain(We will call it example.domain.com) points to the host of our anti-spam/virus gateway appliance. It sends mail to our actual internal SMTP/IMAP/POP production server.

I will setup the zimbra server to have the same example.domain.com and second domain example2.domain.com for the old system to forward too. I would setup an mx record to point example2.domain.com to the new zimbra server. Accounts on the zimbra server will be setup under example.domain.com with an alias to example2.domain.com. When I want email from joe@example.domain.com to be delivered to the new zimbra server I would put a forward on the old email system for joe@example.domain.com to point to joe@example2.domain.com. Assuming this will work am I correct that the to field will retain the joe@example.domain.com address? Another What about email sent from the zimbra server to users that have not been migrated yet. Will the Zimbra server look up the mx and send an email destined for smith@example.domain.com to the gateway device or will it reject the mail because it doesn't have a smith@example.domain.com on the system? Is there a much better way to do all this?

Thanks.

[Baylink]

There is a better way, yes, but I'm not done writing it up for the Wiki (which is mostly because I'm still *implementing* it. :-)

But yes, it involves lots of forwarding to avoid a splash-cut.

[gnyce]

We were in the same setup, roughly, where all mail goes through our av/spam gateway. Using postfix "transports", I distinguished any user that was on Zimbra, and had mail for them go there. All other mail (meaning, if a user/email address was not specified) would go to our legacy/main email server.

On Zimbra, you configure a setting (forget which, but it is in the wiki) to say "if the address used is the same domain but not on here, forward to this server", which was our spam/av gateway, who would then forward over to our other/main email server

on legacy mailserver, if they didn't exist on there, it would get forwardeded to spam/av gateway, which would then relay to Zimbra. It was not bad for a gradual (3 week) migration, and again, this was only about 100 or so people. Is it workable in a larger scale? Yeeessss.... but YMMV.

PM me if you need more specific details, but it is completely workable and functions just fine.