[CentOS] Postfix and virtual mail boxes.

Thu Oct 7 05:48:49 UTC 2021
Gionatan Danti <g.danti at assyoma.it>

Il 2021-10-07 07:18 Rob Kampen ha scritto:
> Hi, not sure this is the best place to go for my problem, but hoping
> someone can point me to the correct or better place.
> I have two currently working CentOS 7 based email servers that host a
> number of virtual domains and users and delivers mail just fine - for
> correctly addressed vmail inboxes AND for alias addressed emails and
> domains.
> These all use postfix, dovecot, amavisd, clamAV, spamassassin, mysql
> (mariadb) and roundcubemail
> I use port 25 for the world email delivery - no auth needed as only
> accepts hosted virtual domain addressed email.
> and
> port 587 for user client MUA to send mail - smtp with STARTTLS auth 
> needed
> port 993 for MUA IMAP access to account mail boxes
> A couple of weeks ago I rolled up a new minimal virtual server (also
> CentOS 7) and basically copied the same setup as the other two and
> have now spent far too long trying to get it going.
> My initial problem was that I  set up mydestination to include
> $mydomain - this has the consequence of seeing any mail@$mydomain as
> local email and trying to deliver to the local machine rather than the
> vmail inboxes.
> So after setting up a new domain just for the MX we moved on.
> All three installations use mysql (mariadb) as the data store for
> domains, alias domains, user vmail accounts, and forwardings (virtual
> alias mapping)
> The mysql bits work just fine as I can send mail from an MUA client
> and they deliver correctly via an authenticated session on port 587 -
> i.e to any world email address AND to local vmail boxes, including
> those addressed via an alias and/or alias domain.
> What fails to work on the new installation, but works fine on my two
> legacy servers, is mail addressed via an alias. Specifically an alias
> domain. Even adding the complete alias email address to the
> forwardings table doesn't work.
> e.g. let's say we have an email domain '@example.com' and an alias
> domain '@example.org'.
> Needed so I can migrate my clients from one server to the other in a
> staged manner.
> Thus the new server is set up to operate as the MX for @example.org
> and @example.com but needs to alias redirect the incoming emails being
> sent to fred at example.org and deliver them to the vmail location for
> fred at example.com (i.e. we have no vmail locations for @example.org
> only for @example.com
> So if I send a test email via my MUA (using port 587 and hence
> authenticated) it does the alias lookups and translations needed and
> correctly delivers the mail.
> However if I send an email to fred at example.org from say a gmail
> account, it arrives at my new server and promptly gets bounced with a
> 550 5.7.1 error - no such email address.
> After doing diff on the main.cf and master.cf from all three servers
> the only differences are the myhostname, mynetworks (new one is dual
> stack IP4/IPv6 and thus includes [::1]/128), smtpd_tls certificate
> names, and the virtual_uid_maps - all expected and accounted for.
> master.cf are identical
> Many dozens of google searches and reading far too many pages, has
> left me with no idea why my new server doesn't accept alias directed
> emails via port 25.
> All the documentation indicates that alias lookups and translations
> are performed by postfix - all the time.
> receive_override_options is not set.
> Any suggestions of things to check or test would be welcome.
> Rob

Hi, can you show the difference on "postconf" output on your 

Danti Gionatan
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