external/ibm-public/postfix/dist/proto/MAILDROP_README.html

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   8 <title>Postfix + Maildrop Howto</title>
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  16 <h1><img src="postfix-logo.jpg" width="203" height="98" ALT="">Postfix + Maildrop Howto</h1>
  17
  18 <hr>
  19
  20 <h2> Introduction </h2>
  21
  22 <p> This document discusses various options to plug the maildrop
  23 delivery agent into Postfix: </p>
  24
  25 <ul>
  26
  27 <li><a href="#direct">Direct delivery without the local delivery agent</a>
  28
  29 <li><a href="#indirect">Indirect delivery via the local delivery agent</a>
  30
  31 <li><a href="#credits">Credits</a>
  32
  33 </ul>
  34
  35 <h2><a name="direct">Direct delivery without the local delivery agent</a></h2>
  36
  37 <p> Postfix can be configured to deliver mail directly to maildrop,
  38 without using the local(8) delivery agent as an intermediate.  This
  39 means that you do not get local aliases(5) expansion or $HOME/.forward
  40 file processing. You would typically do this for hosted domains with
  41 recipients that don't have UNIX home directories. </p>
  42
  43 <p> The following example shows how to use maildrop for some.domain
  44 and for someother.domain. The example comes in two parts. </p>
  45
  46 <p> Part 1 describes changes to the main.cf file: </p>
  47
  48 <blockquote>
  49 <pre>
  50  1 /etc/postfix/main.cf:
  51  2     maildrop_destination_recipient_limit = 1
  52  3     virtual_mailbox_domains = some.domain someother.domain
  53  4     virtual_transport = maildrop
  54  5     virtual_mailbox_maps = hash:/etc/postfix/virtual_mailbox
  55  6     virtual_alias_maps = hash:/etc/postfix/virtual_alias
  56  7
  57  8 /etc/postfix/virtual_mailbox:
  58  9     user1@some.domain        <i>...text here does not matter...</i>
  59 10     user2@some.domain        <i>...text here does not matter...</i>
  60 11     user3@someother.domain   <i>...text here does not matter...</i>
  61 12
  62 13 /etc/postfix/virtual_alias:
  63 14     postmaster@some.domain           postmaster
  64 15     postmaster@someother.domain      postmaster
  65 </pre>
  66 </blockquote>
  67
  68 <ul>
  69
  70 <li> <p> Line 2 is needed so that Postfix will provide one recipient
  71 at a time to the maildrop delivery agent.  </p>
  72
  73 <li> <p> Line 3 informs Postfix that some.domain and someother.domain
  74 are so-called virtual mailbox domains.
  75 Instead of listing the names in main.cf you can also
  76 list them in a file; see the virtual_mailbox_domains documentation for
  77 details. </p>
  78
  79 <li> <p> Line 4 specifies that mail for some.domain and someother.domain
  80 should be delivered by the maildrop delivery agent. </p>
  81
  82 <li> <p> Lines 5 and 8-11 specify what recipients the Postfix SMTP
  83 server should receive mail for. This prevents the mail queue from
  84 becoming clogged with undeliverable messages. Specify an empty
  85 value ("virtual_mailbox_maps =") to disable this feature. </p>
  86
  87 <li> <p> Lines 6 and 13-15 redirect mail for postmaster to the
  88 local postmaster. RFC 821 requires that every domain has a postmaster
  89 address. </p>
  90
  91 </ul>
  92
  93 <p> The vmail userid as used below is the user that maildrop should
  94 run as.  This would be the owner of the virtual mailboxes if they
  95 all have the same owner.  If maildrop is suid (see maildrop
  96 documentation), then maildrop will change to the appropriate owner
  97 to deliver the mail.  </p>
  98
  99 <p> Note: Do not use the postfix user as the maildrop user. </p>
 100
 101 <p> Part 2 describes changes to the master.cf file: </p>
 102
 103 <blockquote>
 104 <pre>
 105 /etc/postfix/master.cf:
 106     maildrop  unix  -       n       n       -       -       pipe
 107       flags=ODRhu user=vmail argv=/path/to/maildrop -d ${recipient}
 108 </pre>
 109 </blockquote>
 110
 111 <p> The pipe(8) manual page gives a detailed description of the
 112 above command line arguments, and more. </p>
 113
 114 <p> If you want to support user+extension@domain style addresses,
 115 use the following instead: </p>
 116
 117 <blockquote>
 118 <pre>
 119 /etc/postfix/master.cf:
 120     maildrop  unix  -       n       n       -       -       pipe
 121       flags=ODRhu user=vmail argv=/path/to/maildrop
 122       -d ${user}@${nexthop} ${extension} ${recipient} ${user} ${nexthop}
 123 </pre>
 124 </blockquote>
 125
 126 <p> The mail is delivered to ${user}@${nexthop} (match key for
 127 maildrop userdb lookup). The ${extension} and the other address
 128 components are available to maildrop rules as $1, $2, $3, ...  and
 129 can be omitted from master.cf or ignored by maildrop when not
 130 needed. </p>
 131
 132 <h2><a name="indirect">Indirect delivery via the local delivery agent</a></h2>
 133
 134 <p> Postfix can be configured to deliver mail to maildrop via the
 135 local delivery agent. This is slightly less efficient than the
 136 "direct" approach discussed above, but gives you the convenience
 137 of local aliases(5) expansion and $HOME/.forward file processing.
 138 You would typically use this for domains that are listed in
 139 mydestination and that have users with a UNIX system account. </p>
 140
 141 <p> To configure maildrop delivery for all UNIX system accounts: </p>
 142
 143 <blockquote>
 144 <pre>
 145 /etc/postfix/main.cf:
 146     mailbox_command = /path/to/maildrop -d ${USER}
 147 </pre>
 148 </blockquote>
 149
 150 <p> Note: ${USER} is spelled in upper case. </p>
 151
 152 <p> To enable maildrop delivery for specific users only, you can
 153 use the Postfix local(8) delivery agent's mailbox_command_maps feature:
 154 </p>
 155
 156 <blockquote>
 157 <pre>
 158 /etc/postfix/main.cf:
 159     mailbox_command_maps = hash:/etc/postfix/mailbox_commands
 160
 161 /etc/postfix/mailbox_commands:
 162     you    /path/to/maildrop -d ${USER}
 163 </pre>
 164 </blockquote>
 165
 166 <p> Maildrop delivery for specific users is also possible by
 167 invoking it from the user's $HOME/.forward file: </p>
 168
 169 <blockquote>
 170 <pre>
 171 /home/you/.forward:
 172     "|/path/to/maildrop -d ${USER}"
 173 </pre>
 174 </blockquote>
 175
 176 <h2><a name="credits">Credits</a></h2>
 177
 178 <ul>
 179
 180 <li> The original text was kindly provided by Russell Mosemann.
 181
 182 <li> Victor Duchovni provided tips for supporting user+foo@domain
 183 addresses.
 184
 185 <li> Tonni Earnshaw contributed text about delivery via the local(8)
 186 delivery agent.
 187
 188 </ul>
 189
 190 </body>
 191
 192 </html>