Relay SMTP Ext to Zimbra. Do you have an idea?

[levithanh0209]

Hi everyone,

English is not my language so I hope the translation will be done

Here, I confront a small problem with Zimbra. As part of the job we need to do some configuration.

The configuration comes down to this

Customer ---> SMTP-Relay (Postfix) -> Zimbra

We are going to make a messaging infrastructure switch, and so that the clients do not receive an SSL alert due to the change of the domain among others, we will put an additional server between the client and the zimbra server.
This server will be used to send requests (SMTP, POP, IMAP) from clients to the Zimbra server. The Zimbra server will send the mails via spamtitan gateway.

For the postfix part of the relay, it's not a problem with the transport table

Code: Select all

* smtp: smtp2.XXX.fr

On the Zimbra we have, I find the main.cf configuration of postfix, especially for LDAP authentication

Code: Select all

virtual_mailbox_maps = proxy: ldap: /opt/zimbra/conf/ldap-vmm.cf
virtual_mailbox_domains = proxy: ldap: /opt/zimbra/conf/ldap-vmd.cf
virtual_alias_maps = proxy: ldap: /opt/zimbra/conf/ldap-vam.cf
virtual_alias_domains = proxy: ldap: /opt/zimbra/conf/ldap-vad.cf
canonical_maps = proxy: ldap: /opt/zimbra/conf/ldap-canonical.cf
transport_maps = proxy: ldap: /opt/zimbra/conf/ldap-transport.cf

I took these files in order to put them on the server "relay"
From this relay server, I can make requests on the LDAP of Zimbra, and the postfix relay is well connected in LDAP on Zimbra.

My problem is the following (As it is an internal test server, I have not yet configure the SSL / TLS):

I have the impression that the SMTP manages some of the authentication, but not totally, especially password level.

Here are the tests I could do

Test 1:
- Telnet connection on the relay server
- Authentication with my zimbra user
- USER Correct
- PASS Correct
-> 235 2.7.0 Authentication successful

Test 2:
- Telnet connection on the relay server
- Authentication with my zimbra user
- USER Correct
- PASSE Not Correct
-> 235 2.7.0 Authentication successful

Test 3:
- Telnet connection on the relay server
- Authentication with my zimbra user
- USER Not Correct
- PASSE Not Correct
-> 535 5.7.8 Error: authentication failed: authentication failure


Do you have an idea of ​​if already technically it is feasible?
Do you have any leads for an external postfix to handle user authentication for Zimbra's ldap database?

Thank you very much !
Vi Thanh.