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solution to local lack-of-aliasing problem
 
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<hide>
[[page type::article]]
[[thing type::software]]
[[software type::mail transfer agent]]
[[architecture::server]]
[[license::open source]]
[[category:software]]
</hide>
==About==
==About==
[[category:software]][[Postfix]] is an [[open-source]] [[mail transfer agent]] (MTA) for [[POSIX]] systems. It is fully supported by [[Webmin]] and is part of the [[Dovecot]] stack.
[[Postfix]] is an [[open source]] [[mail transfer agent]] (MTA) for [[POSIX]] systems. It is fully supported by [[Webmin]]/[[VirtualMin]] and is part of the [[Dovecot]] stack.
==Notes==
===Pages===
After making changes to the Postfix configuration files, you don't actually have to stop and restart Postfix to load the changes; you can just type (as root) "postfix reload".
* [[/aliasing]]: managing email redirects/aliases
===flow===
* [[/fixing]]: diagnosis of installations that aren't working right
There are multiple stages inside Postfix, and each stage can be affected by configuration parameters. I have not yet found a clear documentation of the data flow, but it seems to go like this (only much more complicated) under normal circumstances:
* see also: [[DKIM]], [[DMARC]], [[Sender Policy Framework]] (SPF)
* [[/chroot]]: running Postfix in a [[chroot]]ed environment


: [[SMTP]] &rarr; Postfix delivery queue &rarr; user alias mappings &rarr; [[mail delivery agent|local delivery]] (MDA, e.g. [[Dovecot]])
===Files===
* [[/main.cf]]
* [[/master.cf]]: formatted list of transport helper applications
* [[/mail.log]] (typically found in /var/log)
===Internal Apps===
* [[/aliases]] ([http://www.postfix.org/aliases.5.html reference])
* [[/cleanup]] ([http://postfix.org/cleanup.8.html reference])
* [[/lmtp]] ([http://postfix.org/lmtp.8.html reference])
* [[/local]] ([http://postfix.org/local.8.html reference])
* [[/pickup]] ([http://postfix.org/pickup.8.html reference])
* [[/qmgr]] ([http://postfix.org/qmgr.8.html reference])
* [[/smtpd]] ([http://postfix.org/smtpd.8.html reference])
* [[/transport]] ([http://www.postfix.org/transport.5.html reference])
* [[/trivial-rewrite]] ([http://postfix.org/trivial-rewrite.8.html reference]))
===User Applets===
* [[/newaliases]]
===Other Applets===
These are installed as part of the postfix package; not sure how they should be classified:
{|
|-
| valign=top |
* '''/usr/bin''':
** [[/mailq]]
** [[/newaliases]] - user utility
** [[/rmail]]
* '''/usr/lib''':
** [[/postfix_groups.pl]]
** [[/sendmail]]
| valign=top |
* '''/usr/lib/postfix''':
** [[/anvil]]
** [[/bounce]]
** [[/cleanup]]
** [[/discard]]
** [[/error]]
** [[/flush]]
** [[/fsstone]]
** [[/lmtp]]
** [[/local]]
** [[/master]]
** [[/oqmgr]]
** [[/pickup]]
** [[/pipe]]
** [[/post-install]]
** [[/postfix-files]]
** [[/postfix-script]]
** [[/postfix-wrapper]]
** [[/postmulti-script]]
** [[/proxymap]]
** [[/qmgr]]
** [[/qmqpd]]
** [[/scache]]
** [[/showq]]
** [[/smtp]]
** [[/smtpd]]
** [[/spawn]]
** [[/tlsmgr]]
** [[/trivial-rewrite]]
** [[/verify]]
** [[/virtual]]
| valign=top |
* '''/usr/sbin''':
** [[/postalias]]
** [[/postcat]]
** [[/postconf]]
** [[/postdrop]]
** [[/postfix]] - core binary
** [[/postfix-add-filter]]
** [[/postfix-add-policy]]
** [[/postkick]]
** [[/postlock]]
** [[/postlog]]
** [[/postmap]]
** [[/postmulti]]
** [[/postqueue]]
** [[/postsuper]]
** [[/qmqp-sink]]
** [[/qmqp-source]]
** [[/qshape]]
** [[/rmail]]
** [[/sendmail]]
** [[/smtp-sink]]
** [[/smtp-source]]
|}


However, when using virtual (non-system) users, internally-generated emails (e.g. mail from [[cron]] or [[PHP]]'s mail() function) seem to bypass the alias mappings, which the MDA then rejects if they are addressed to an alias instead of a user.
===Error Messages===
* [[503 5.5.1 Error: authentication not enabled]]
* [[Connect to private/dovecot-auth failed: No such file or directory]]


A table from the official documentation is more detailed, if perhaps less clear (where does the message ''end up''? qmgr? how does it get delivered?):
===Other Subpages===
<table align=center>
* [[/flow]]: the flow of messages across the various helper programs that make up Postfix
<tr>
* [[/SSL]]: Postfix and SSL
<td colspan="2"> </td>
<td align="center" bgcolor="#f0f0ff"> [http://postfix.org/trivial-rewrite.8.html trivial-<br>rewrite(8)]<br>(std
form) </td>
<td colspan="5"> </td>
<td align="center" bgcolor="#f0f0ff"> [http://postfix.org/trivial-rewrite.8.html trivial-<br>rewrite(8)]<br>(resolve)
</td>
</tr>
<tr>
<td colspan="2"> </td>
<td align="center"><table><tr><td align="center"> ^<br> <tt> |
</tt> </td><td align="center"> <tt> |<br>v </tt> </td></tr></table>
</td><td colspan="5"> </td>
<td align="center"><table><tr><td align="center"> ^<br> <tt> |
</tt> </td><td align="center"> <tt> |<br>v </tt> </td></tr></table>
</td><td colspan="2"> </td>
</tr>
<tr>
<td valign="middle" align="center" bgcolor="#f0f0ff"> [http://postfix.org/smtpd.8.html smtpd(8)]
</td>
<td rowspan="3" valign="middle" align="center"> <tt> &gt;- </tt>
</td>
<td rowspan="3" align="center" bgcolor="#f0f0ff"> [http://postfix.org/cleanup.8.html cleanup(8)] </td>
<td rowspan="3" valign="middle" align="center"> <tt> -&gt; </tt>
</td>
<td rowspan="3" align="center" bgcolor="#f0f0ff"> [http://postfix.org/QSHAPE_README.html#incoming_queue incoming] </td>
<td rowspan="3" valign="middle" align="center"> <tt> -&gt; </tt>
</td>
<td rowspan="3" align="center" bgcolor="#f0f0ff"> [http://postfix.org/QSHAPE_README.html#active_queue active] </td>
<td rowspan="3" valign="middle" align="center"> <tt> -&gt; </tt>
</td>
<td rowspan="3" align="center" bgcolor="#f0f0ff"> [http://postfix.org/qmgr.8.html qmgr(8)]</td>
<td rowspan="3" valign="middle" align="center"> <tt> -&lt; </tt>
</td>
<td valign="middle" align="center" bgcolor="#f0f0ff">
[http://postfix.org/smtp.8.html smtp(8)]</td>
</tr>
<tr>
<td valign="middle" align="center" bgcolor="#f0f0ff">
[http://postfix.org/qmqpd.8.html qmqpd(8)]</td>
<td valign="middle" align="center" bgcolor="#f0f0ff"> [http://postfix.org/lmtp.8.html lmtp(8)]</td>
</tr>
<tr>
<td valign="middle" align="center" bgcolor="#f0f0ff"> [http://postfix.org/pickup.8.html pickup(8)]
</td>
<td valign="middle" align="center" bgcolor="#f0f0ff"> [http://postfix.org/local.8.html local(8)]
</td>
</tr>
<tr>
<td colspan="2"> </td>
<td align="center"> ^<br> <tt> | </tt> </td>
<td colspan="3"> </td>
<td align="center"><table><tr><td align="center"> ^<br> <tt> |
</tt> </td><td align="center"> <tt> |<br>v </tt> </td></tr></table>
</td><td colspan="4"> </td>
</tr>
<tr>
<td colspan="2"> </td>
<td align="center"> bounces<br> forwarding<br> notices</td>
<td colspan="3"> </td>
<td align="center" bgcolor="#f0f0ff"> [http://postfix.org/QSHAPE_README.html#deferred_queue deferred]
</td><td colspan="2"> </td>
</tr>
</table>
===aliases===
To set up aliases, either edit the file specified by the [[/main.cf/alias_maps|alias_maps]] setting in [[/main.cf|main.cf]] ([[etc/aliases|/etc/aliases]] by default) and then run [[newaliases]] (or "postalias /etc/aliases") to update the database, or else use [[Webmin]] ("Mail Aliases" icon, then click on the "Create a new alias" link).


'''Notes''':
==Notes==
* Webmin seems to automatically run newaliases when you add or modify an individual alias, but ''not'' when you use it to edit the [[etc/aliases|/etc/aliases]] file directly. Changes made to /etc/aliases will not take effect until the database is updated.
After making changes to the Postfix configuration files, you don't actually have to stop and restart Postfix to load the changes; you can just type (as root) "postfix reload".
* Stopping and starting the postfix daemon does ''not'' update from the aliases file; you still have to run newaliases.
* If emails ''from outside'' are properly forwarded to their aliases but ''locally generated'' emails are "returned" as undeliverable with the error message "Diagnostic-Code: x-unix; user unknown", then make the following change in main.cf:
** '''change''': {{link/subpage|pfx=/main.cf/|receive_override_options}} = no_address_mappings
** '''to this''': receive_override_options =
===catch-all===
To set up a catch-all address, edit {{link/subpage|main.cf}} and set the following parameters:
* {{link/subpage|pfx=/main.cf/|local_recipient_maps}} =
* {{link/subpage|pfx=/main.cf/|luser_relay}} = <u>whereToSend</u>


The syntax for <u>whereToSend</u> is explained [http://www.postfix.org/postconf.5.html#luser_relay here].
Examples:
* luser_relay = $user@anotherdomain.org
** forwards all email addressed to "invaliduser@firstdomain.org" to "invaliduser@anotherdomain.org"
* luser_relay = youraddress@anotherdomain.org
** forwards all email addressed to invalid users to "youraddress@anotherdomain.org".
===automatic BCC===
===automatic BCC===
To automatically [[blind carbon copy|BCC]] outgoing mail ''from'' any given set of users, set [[/main.cf/sender_bcc_maps|sender_bcc_maps]] in [[/main.cf]] to <u>hash:/etc/postfix/sender_bcc</u>. (In [[Webmin]]: BCC Mapping: Sender BCC mapping lookup tables)
To automatically [[blind carbon copy|BCC]] outgoing mail ''from'' any given set of users, set [[/main.cf/sender_bcc_maps|sender_bcc_maps]] in [[/main.cf]] to <u>hash:/etc/postfix/sender_bcc</u>. (In [[Webmin]]: BCC Mapping: Sender BCC mapping lookup tables)
Line 102: Line 116:
Each line in the [[/sender_bcc]] file will contain the ''sender'' (which can be user@domain, user, or @domain), one or more blanks, then the ''recipient'' (which can be one address or multiple addresses separated by commas).
Each line in the [[/sender_bcc]] file will contain the ''sender'' (which can be user@domain, user, or @domain), one or more blanks, then the ''recipient'' (which can be one address or multiple addresses separated by commas).


Example -- BCCs all mail sent by somedomain.com users to an archive address:
Example -- BCCs all mail sent by vbz.com users to an archive address:
  @vbz.com archive{{CURRENTYEAR}}@vbz.com
  @vbz.com archive{{CURRENTYEAR}}@vbz.com
===pages to index===
===pages to index===
I have these open in tabs, so they are probably relevant to something:
Possibly useful pages:
* [https://www.howtoforge.com/postfix_backup_mx Setting Up Postfix As A Backup MX]
* [http://www.postfix.org/ADDRESS_REWRITING_README.html Postfix Address Rewriting]
* [http://www.postfix.org/ADDRESS_REWRITING_README.html Postfix Address Rewriting]
* [http://www.postfix.org/trivial-rewrite.8.html trivial-rewrite] (manpage)
* [http://www.postfix.org/trivial-rewrite.8.html trivial-rewrite] (manpage)
* [http://www.postfix.org/postconf.5.html Postfix Configuration Parameters] (includes [[/main.cf]] parameters)
* [http://www.postfix.org/postconf.5.html Postfix Configuration Parameters] (includes [[/main.cf]] parameters)
* [http://www.postfix.org/FILTER_README.html Postfix After-Queue Content Filter]
* [http://www.group-office.com/wiki/Mailserver Group-Office Mailserver] plugin: helps administer Postfix
* [http://en.gentoo-wiki.com/wiki/Mail_server_using_Postfix_and_Dovecot Mail server using Postfix and Dovecot] on [[Gentoo Linux]]
==Links==
==Links==
===Official===
===Official===
* [http://www.postfix.org/ postfix.org]
* [http://www.postfix.org/ home page]
* {{link/manpage/only|Postfix|manpage}}
 
===Reference===
===Reference===
* {{wikipedia|Postfix (software)}}
* {{wikipedia|Postfix (software)}}
* [http://www.postfix.org/ home page]
* [http://postfix.wiki.xs4all.nl/ wiki]
** [http://postfix.wiki.xs4all.nl/index.php?title=Relay_recipient_maps_using_LDAP_against_Active_Directory Relay recipient maps using LDAP against Active Directory]

Latest revision as of 16:00, 17 September 2021

<hide> page type::article thing type::software software type::mail transfer agent architecture::server license::open source </hide>

About

Postfix is an open source mail transfer agent (MTA) for POSIX systems. It is fully supported by Webmin/VirtualMin and is part of the Dovecot stack.

Pages

Files

Internal Apps

User Applets

Other Applets

These are installed as part of the postfix package; not sure how they should be classified:

Error Messages

Other Subpages

  • /flow: the flow of messages across the various helper programs that make up Postfix
  • /SSL: Postfix and SSL

Notes

After making changes to the Postfix configuration files, you don't actually have to stop and restart Postfix to load the changes; you can just type (as root) "postfix reload".

automatic BCC

To automatically BCC outgoing mail from any given set of users, set sender_bcc_maps in /main.cf to hash:/etc/postfix/sender_bcc. (In Webmin: BCC Mapping: Sender BCC mapping lookup tables)

Each line in the /sender_bcc file will contain the sender (which can be user@domain, user, or @domain), one or more blanks, then the recipient (which can be one address or multiple addresses separated by commas).

Example -- BCCs all mail sent by vbz.com users to an archive address: 

@vbz.com archive2026@vbz.com

pages to index

Possibly useful pages:

Official

Reference

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