Zimbra and Exchange deliver to both

[Jotunn]

Hello,

We are evaluating Zimbra, currently using Exchange 2003. I need to have Exchange and Zimbra running side by side, delivering email to both servers. This deployment is at a single location for a single domain. Any thoughts on how to accomplish this? I did find this in the wiki which is close. I know that by having this users sending from Zimbra will not see the sent email in exchange and visa versa but that is ok.

Thanks in advance.

Cheers,

[shmiv]

We needed to do the same before moving to production and used the following:

1. Put Zimbra on a test domain only available on our network (zimbra.domainTEST.com)

2. Created user on Zimbra using test domain (user@domainTEST.com)

3. Created aliases (Custom Recipients) in Exchange (5.5) that pointed to users on test domain.

4. Used Alternative Recipients in real Exchange users to deliver to Custom Recipient. NOTE that in 5.5 you must select "Deliver message to both.."

5. Added MX record to our internal dns pointing to domainTEST.com.

Probably not the most elegant solution, but it worked for us.

[Jotunn]

Thanks for the reply shmiv.

The "aliases" idea looks like a good one.

I decided to go a different route and put another MTA agent in the mix acting as an inbound relay server pointing to both Z and E. This way Zimbra is 100% ready to go and all I have to do is kill the relay server at some point.

I will post back once I have it up and running.

Cheers,

[blumanfry]

Thanks for the reply shmiv.

The "aliases" idea looks like a good one.

I decided to go a different route and put another MTA agent in the mix acting as an inbound relay server pointing to both Z and E. This way Zimbra is 100% ready to go and all I have to do is kill the relay server at some point.

I will post back once I have it up and running.

Cheers,

Hi Jotunn,

I was just wondering what your success was with this manner? Can I ask how you setup the inbound MTA to split the domain and sent to both Z and E servers at once? I am looking at setting up a SMTP relay on the inbound, but I just wanted to know what your configuration was and if it worked well for you?

Thank you for any help.

[gilly05]

I think this works... if you setup a postfix MTA in front of both servers, you should be able to have it send the mail to both by adding these lines to your main.cf (once you've setup the proper relay for the first server):

milter_default_action = tempfail
smtpd_milters = inet:"ip of second server"

The only problem that I have run into on this is that if the "second server" goes down (or is taken down for some reason), postfix just errors and doesn't continue to relay to the "first server".

I hope that makes sense. As a practical example, I use a postfox-based spam/virus filter that relays mail for my Exchange server. I wanted to test Zimbra, so I added these lines to my postfix filter's main.cf file. This allowed me to get the email to both servers. But, if I take down the test Zimbra server at all, the postfix filter stops relaying messages to my Exchange server.

Moral of the story: if you do this, be sure to remove the lines and do a "postfix reload" before you take the "other" server down.

I hope that helps.

[gilly05]

Ok... so I am now having problems with this, as seen in this post. But I think the better option for this type of implementation would be to have the mail directed to Zimbra to begin with, then put the smtpd_milter lines in the /opt/zimbra/postfix/conf/main.cf file pointing it to your exchange server. This might work... I may try this over the next couple of days. I will report back with the results.