Zimbra and MTA

[klxout]

Hello,

We are using Zimbra as mailbox and all is working ok, but now we need to configure 1 (or two) additional Zimbra server as mta, we need that this server receives all external mail to mailbox server.
I have made some test and i detected that if I configure as mta role with zimbra, then I have a problem if mailbox/ldap is stopped, then mta can't receives any mail and we lost all HA environment -we can't install additional ldap at this momment-. I have detected that mta try to connect to ldap, it seems that try to check is destination address exist.

For security and with previous described problem we think that best solution is to install Zimbra mta as standalone server, and then configure to forward (relay) mail of this domain to mailbox -I have checked and this works-, but with this when is sended a mail to an account that for example not exists return mail is sended for mailbox, and with mta ldap integration seems that mail is sended for mta, and use less resource because is using mta to answer and this mails.

How can I do this with zimbra standalone with mta, is configurable zimbra postfix to read a file or similar that can contains a synchronized a valid user of zimbra?

Ho can I recover users of zimbra to create this script? How can I configure this in postfix?

Thanks

[StephaneP]

The best way to acheive some kind of H/A would be to setup a replicated LDAP near the MTAs. If for some reason the mailbox server is not available, the MTAs will queue the messages for future delivery without requiring any extra hop.

[klxout]

At this moment I can't install a replicated LDAP.
It is possible to install mta as standalone server, and this server could get a list of user (for example an scheduled script that exports users from ldap to mta standalone).
If is not possible what problems can cause this extra hop?

Thanks

[StephaneP]

A Zimbra's MTA would by default require to link to the LDAP for routing incoming emails to the relevant mailstore. As far as I know, there is no easy way to have it using an alternate transport map while staying in Zimbra's design (zimbra would rewrite the various Postfix config files). So what you can do is deploying a regular Postfix router and use a script that will extract a user list from LDAP or Mailstore (using zmprov for example) for generating the relevant transport map so the router will relay all incoming emails to Zimbra.

The counter parts:
- This server would not be managed by Zimbra anymore
- Your script would have to be run any time there is a change in users list

That's why the LDAP replicate way would be easier to maintain and operate.

Hope this helps

[klxout]

Ok, you are on right, this is I have planned
Only ones question, I can obtain users and distribution lists with zmprov? What parameters I have to change in postfix to read this file generated? At this moment I don't know what parameter configure this transport map
Can you giver more infomration about export users/distributions lists and config in postfix/zimbra

Thanks

A Zimbra's MTA would by default require to link to the LDAP for routing incoming emails to the relevant mailstore. As far as I know, there is no easy way to have it using an alternate transport map while staying in Zimbra's design (zimbra would rewrite the various Postfix config files). So what you can do is deploying a regular Postfix router and use a script that will extract a user list from LDAP or Mailstore (using zmprov for example) for generating the relevant transport map so the router will relay all incoming emails to Zimbra.

The counter parts:
- This server would not be managed by Zimbra anymore
- Your script would have to be run any time there is a change in users list

That's why the LDAP replicate way would be easier to maintain and operate.

Hope this helps