Dear Zhang,
1. in which files so you can try to tune the per-user transport to "lmtp:[server]:24"?
2. make a sample of 2 user on how to make per-user transport

Thanks
Napoleon

Dear Zhang,
  the document is hard to understand, please guide me

As for this information I found. the testing environment should be
Server A - User 1, User 2 & User 3
Server B - User 4, User 6

Both installation using domain example.com and that i should config to have when i am on Server A as user 1, I send a email to User 4. the mail should arrived successfully on Server B and vise versa

Dear Zhang,
1. LDAP attributes using iredadmin - pro ?
2. let said 192.168.1.1 is the mail server Mail 1 in this example http://wiki.zarafa.com/index.php/Postfi … rver_setup
which is the server to received email, and mail2 mail3 mail4 users send mail to outside is thru mail1, my question is how do i do that?

3. I follow some hints you give me https://docs.iredmail.org/per-account.transport.html
    using iredadmin i create all the users in our domain, and configure relay on user that is not on the sites to the server it belong, it worked! but i don't know if it is the correct way.

Thanks
Napoleon

Dear Zhang,

  I got this error on mail log of Mail 1
  relay=none, delay=536, delays=535/1/0/0.05, dsn=4.3.0, status=deferred (unknown mail transport error)

after i add the IP address of server A in Postfix /etc/postfix/main.cf on Server B (Server B is Mail 1 on our discussion)
by the advise below
https://forum.iredmail.org/topic12145-i … mmand.html

thanks
Napoleon

this is my configuration, it should be dovecot i Think

You did it wrong.

"Relay received mail to" should be something like: "lmtp:inet:[ip-of-destination-server]:24" (without quotes).

- "Relay received mail to -> lmtp:inet:10.8.0.154:24
- Leave "Relay outgoing email to" empty.

1: Is server with IP address "10.8.0.154" running?
2: Again, check /etc/dovecot/dovecot.conf, make sure LMTP service is listening on 0.0.0.0, so that server A/B can connect and deliver emails to each other.

inet_listener lmtp {
        # Listen on localhost (ipv4)
        #address = 127.0.0.1
        address = 0.0.0.0
        port = 24
    }
set on both /etc/dovecot/dovecot.conf
have restart the dovecot service by systemctl restart dovecot
but still mail 1 could not send to mail 2

Log from Mail 1 (mail 1 to mail 2)

Dec  6 15:30:09 ct-mailsites2 postfix/amavis/smtp[1311]: 12A0140BD4: to=<mario.lee@aaa.com>, relay=127.0.0.1[127.0.0.1]:10026, delay=1.2, delays=0.17/0.04/0/0.98, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 1973B40C71)
Dec  6 15:30:09 ct-mailsites2 postfix/qmgr[807]: 12A0140BD4: removed
Dec  6 15:30:09 ct-mailsites2 postfix/smtp[1322]: Untrusted TLS connection established to 10.8.0.159[10.8.0.159]:25: TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
Dec  6 15:30:09 ct-mailsites2 postfix/smtp[1322]: 1973B40C71: to=<mario.lee@aaa.com>, relay=10.8.0.159[10.8.0.159]:25, delay=0.52, delays=0.06/0.06/0.23/0.18, dsn=2.0.0, status=sent (250 2.0.0 Ok: queued as 8C3C741738)
Dec  6 15:30:09 ct-mailsites2 postfix/qmgr[807]: 1973B40C71: removed

Log from mail 2 (the recipient server)

Dec  6 15:31:57 ct-mailsitesTX postfix/qmgr[861]: 746B541799: from=<napoleon.lam@aaa.com>, size=2687, nrcpt=1 (queue active)
Dec  6 15:31:57 ct-mailsitesTX postfix/qmgr[861]: 981EA41797: from=<napoleon.lam@aaa.com>, size=2687, nrcpt=1 (queue active)
Dec  6 15:31:57 ct-mailsitesTX postfix/qmgr[861]: 0929B41796: from=<napoleon.lam@aaa.com>, size=2693, nrcpt=1 (queue active)
Dec  6 15:31:58 ct-mailsitesTX postfix/lmtp[1392]: connect to 10.8.0.154[10.8.0.154]:24: No route to host
Dec  6 15:31:58 ct-mailsitesTX postfix/lmtp[1391]: connect to 10.8.0.154[10.8.0.154]:24: No route to host
Dec  6 15:31:58 ct-mailsitesTX postfix/lmtp[1390]: connect to 10.8.0.154[10.8.0.154]:24: No route to host
Dec  6 15:31:58 ct-mailsitesTX postfix/lmtp[1391]: 981EA41797: to=<mario.lee@aaa.com>, relay=none, delay=977, delays=976/0.01/1/0, dsn=4.4.1, status=deferred (connect to 10.8.0.154[10.8.0.154]:24: No route to host)
Dec  6 15:31:58 ct-mailsitesTX postfix/lmtp[1392]: 0929B41796: to=<mario.lee@aaa.com>, relay=none, delay=1004, delays=1003/0.02/1/0, dsn=4.4.1, status=deferred (connect to 10.8.0.154[10.8.0.154]:24: No route to host)
Dec  6 15:31:58 ct-mailsitesTX postfix/lmtp[1390]: 746B541799: to=<mario.lee@aaa.com>, relay=none, delay=532, delays=531/0.02/1/0, dsn=4.4.1, status=deferred (connect to 10.8.0.154[10.8.0.154]:24: No route to host)
Dec  6 15:33:29 ct-mailsitesTX postfix/anvil[1302]: statistics: max connection rate 1/60s for (smtpd:10.8.0.154) at Dec  6 15:30:09
Dec  6 15:33:29 ct-mailsitesTX postfix/anvil[1302]: statistics: max connection count 1 for (smtpd:10.8.0.154) at Dec  6 15:30:09
Dec  6 15:33:29 ct-mailsitesTX postfix/anvil[1302]: statistics: max cache size 1 at Dec  6 15:30:09

I have learned that the setup is other else to have it worked.
it just configure the right setting on relay. no need to involved lmtp

Thanks Zhang for your support.

Please look at above on my setting on 2018-11-30 09:29:52 (the 2 images) I am sure i have reboot the server.

I changes back, and it worked all the way. i don't know why there is problem on that day, but it should be that setting.
I did not used lmtp presently and it work just as i expected.

Thanks anyway
Napoleon