/usr/share/doc/postfix/html/virtual.5.html is in postfix-doc 2.9.6-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 | <!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html> <head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<title> Postfix manual - virtual(5) </title>
</head> <body> <pre>
VIRTUAL(5) VIRTUAL(5)
<b>NAME</b>
virtual - Postfix virtual alias table format
<b>SYNOPSIS</b>
<b>postmap /etc/postfix/virtual</b>
<b>postmap -q "</b><i>string</i><b>" /etc/postfix/virtual</b>
<b>postmap -q - /etc/postfix/virtual</b> <<i>inputfile</i>
<b>DESCRIPTION</b>
The optional <a href="virtual.5.html"><b>virtual</b>(5)</a> alias table rewrites recipient
addresses for all local, all virtual, and all remote mail
destinations. This is unlike the <a href="aliases.5.html"><b>aliases</b>(5)</a> table which
is used only for <a href="local.8.html"><b>local</b>(8)</a> delivery. Virtual aliasing is
recursive, and is implemented by the Postfix <a href="cleanup.8.html"><b>cleanup</b>(8)</a>
daemon before mail is queued.
The main applications of virtual aliasing are:
<b>o</b> To redirect mail for one address to one or more
addresses.
<b>o</b> To implement virtual alias domains where all
addresses are aliased to addresses in other
domains.
Virtual alias domains are not to be confused with
the <a href="ADDRESS_CLASS_README.html#virtual_mailbox_class">virtual mailbox domains</a> that are implemented
with the Postfix <a href="virtual.8.html"><b>virtual</b>(8)</a> mail delivery agent.
With virtual mailbox domains, each recipient
address can have its own mailbox.
Virtual aliasing is applied only to recipient envelope
addresses, and does not affect message headers. Use
<a href="canonical.5.html"><b>canonical</b>(5)</a> mapping to rewrite header and envelope
addresses in general.
Normally, the <a href="virtual.5.html"><b>virtual</b>(5)</a> alias table is specified as a
text file that serves as input to the <a href="postmap.1.html"><b>postmap</b>(1)</a> command.
The result, an indexed file in <b>dbm</b> or <b>db</b> format, is used
for fast searching by the mail system. Execute the command
"<b>postmap /etc/postfix/virtual</b>" to rebuild an indexed file
after changing the corresponding text file.
When the table is provided via other means such as NIS,
LDAP or SQL, the same lookups are done as for ordinary
indexed files.
Alternatively, the table can be provided as a regular-
expression map where patterns are given as regular expres-
sions, or lookups can be directed to TCP-based server. In
those case, the lookups are done in a slightly different
way as described below under "REGULAR EXPRESSION TABLES"
or "TCP-BASED TABLES".
<b>CASE FOLDING</b>
The search string is folded to lowercase before database
lookup. As of Postfix 2.3, the search string is not case
folded with database types such as <a href="regexp_table.5.html">regexp</a>: or <a href="pcre_table.5.html">pcre</a>: whose
lookup fields can match both upper and lower case.
<b>TABLE FORMAT</b>
The input format for the <a href="postmap.1.html"><b>postmap</b>(1)</a> command is as follows:
<i>pattern result</i>
When <i>pattern</i> matches a mail address, replace it by
the corresponding <i>result</i>.
blank lines and comments
Empty lines and whitespace-only lines are ignored,
as are lines whose first non-whitespace character
is a `#'.
multi-line text
A logical line starts with non-whitespace text. A
line that starts with whitespace continues a logi-
cal line.
<b>TABLE SEARCH ORDER</b>
With lookups from indexed files such as DB or DBM, or from
networked tables such as NIS, LDAP or SQL, patterns are
tried in the order as listed below:
<i>user</i>@<i>domain address, address, ...</i>
Redirect mail for <i>user</i>@<i>domain</i> to <i>address</i>. This
form has the highest precedence.
<i>user address, address, ...</i>
Redirect mail for <i>user</i>@<i>site</i> to <i>address</i> when <i>site</i> is
equal to $<b><a href="postconf.5.html#myorigin">myorigin</a></b>, when <i>site</i> is listed in $<b><a href="postconf.5.html#mydestination">mydes</a>-</b>
<b><a href="postconf.5.html#mydestination">tination</a></b>, or when it is listed in $<b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a></b>
or $<b><a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a></b>.
This functionality overlaps with functionality of
the local <i>aliases</i>(5) database. The difference is
that <a href="virtual.5.html"><b>virtual</b>(5)</a> mapping can be applied to non-local
addresses.
@<i>domain address, address, ...</i>
Redirect mail for other users in <i>domain</i> to <i>address</i>.
This form has the lowest precedence.
Note: @<i>domain</i> is a wild-card. With this form, the
Postfix SMTP server accepts mail for any recipient
in <i>domain</i>, regardless of whether that recipient
exists. This may turn your mail system into a
backscatter source: Postfix first accepts mail for
non-existent recipients and then tries to return
that mail as "undeliverable" to the often forged
sender address.
<b>RESULT ADDRESS REWRITING</b>
The lookup result is subject to address rewriting:
<b>o</b> When the result has the form @<i>otherdomain</i>, the
result becomes the same <i>user</i> in <i>otherdomain</i>. This
works only for the first address in a multi-address
lookup result.
<b>o</b> When "<b><a href="postconf.5.html#append_at_myorigin">append_at_myorigin</a>=yes</b>", append "<b>@$<a href="postconf.5.html#myorigin">myorigin</a></b>"
to addresses without "@domain".
<b>o</b> When "<b><a href="postconf.5.html#append_dot_mydomain">append_dot_mydomain</a>=yes</b>", append "<b>.$<a href="postconf.5.html#mydomain">mydomain</a></b>"
to addresses without ".domain".
<b>ADDRESS EXTENSION</b>
When a mail address localpart contains the optional recip-
ient delimiter (e.g., <i>user+foo</i>@<i>domain</i>), the lookup order
becomes: <i>user+foo</i>@<i>domain</i>, <i>user</i>@<i>domain</i>, <i>user+foo</i>, <i>user</i>, and
@<i>domain</i>.
The <b><a href="postconf.5.html#propagate_unmatched_extensions">propagate_unmatched_extensions</a></b> parameter controls
whether an unmatched address extension (<i>+foo</i>) is propa-
gated to the result of table lookup.
<b>VIRTUAL ALIAS DOMAINS</b>
Besides virtual aliases, the virtual alias table can also
be used to implement <a href="ADDRESS_CLASS_README.html#virtual_alias_class">virtual alias domains</a>. With a virtual
alias domain, all recipient addresses are aliased to
addresses in other domains.
Virtual alias domains are not to be confused with the vir-
tual mailbox domains that are implemented with the Postfix
<a href="virtual.8.html"><b>virtual</b>(8)</a> mail delivery agent. With virtual mailbox
domains, each recipient address can have its own mailbox.
With a virtual alias domain, the virtual domain has its
own user name space. Local (i.e. non-virtual) usernames
are not visible in a <a href="ADDRESS_CLASS_README.html#virtual_alias_class">virtual alias domain</a>. In particular,
local <a href="aliases.5.html"><b>aliases</b>(5)</a> and local mailing lists are not visible
as <i>localname@virtual-alias.domain</i>.
Support for a <a href="ADDRESS_CLASS_README.html#virtual_alias_class">virtual alias domain</a> looks like:
/etc/postfix/<a href="postconf.5.html">main.cf</a>:
<a href="postconf.5.html#virtual_alias_maps">virtual_alias_maps</a> = hash:/etc/postfix/virtual
Note: some systems use <b>dbm</b> databases instead of <b>hash</b>. See
the output from "<b>postconf -m</b>" for available database
types.
/etc/postfix/virtual:
<i>virtual-alias.domain anything</i> (right-hand content does not matter)
<i>postmaster@virtual-alias.domain postmaster</i>
<i>user1@virtual-alias.domain address1</i>
<i>user2@virtual-alias.domain address2, address3</i>
The <i>virtual-alias.domain anything</i> entry is required for a
<a href="ADDRESS_CLASS_README.html#virtual_alias_class">virtual alias domain</a>. <b>Without this entry, mail is rejected</b>
<b>with "relay access denied", or bounces with "mail loops</b>
<b>back to myself".</b>
Do not specify <a href="ADDRESS_CLASS_README.html#virtual_alias_class">virtual alias domain</a> names in the <a href="postconf.5.html"><b>main.cf</b></a>
<b><a href="postconf.5.html#mydestination">mydestination</a></b> or <b><a href="postconf.5.html#relay_domains">relay_domains</a></b> configuration parameters.
With a virtual alias domain, the Postfix SMTP server
accepts mail for <i>known-user@virtual-alias.domain</i>, and
rejects mail for <i>unknown-user</i>@<i>virtual-alias.domain</i> as
undeliverable.
Instead of specifying the virtual alias domain name via
the <b><a href="postconf.5.html#virtual_alias_maps">virtual_alias_maps</a></b> table, you may also specify it via
the <a href="postconf.5.html"><b>main.cf</a> <a href="postconf.5.html#virtual_alias_domains">virtual_alias_domains</a></b> configuration parameter.
This latter parameter uses the same syntax as the <a href="postconf.5.html"><b>main.cf</b></a>
<b><a href="postconf.5.html#mydestination">mydestination</a></b> configuration parameter.
<b>REGULAR EXPRESSION TABLES</b>
This section describes how the table lookups change when
the table is given in the form of regular expressions. For
a description of regular expression lookup table syntax,
see <a href="regexp_table.5.html"><b>regexp_table</b>(5)</a> or <a href="pcre_table.5.html"><b>pcre_table</b>(5)</a>.
Each pattern is a regular expression that is applied to
the entire address being looked up. Thus, <i>user@domain</i> mail
addresses are not broken up into their <i>user</i> and <i>@domain</i>
constituent parts, nor is <i>user+foo</i> broken up into <i>user</i> and
<i>foo</i>.
Patterns are applied in the order as specified in the ta-
ble, until a pattern is found that matches the search
string.
Results are the same as with indexed file lookups, with
the additional feature that parenthesized substrings from
the pattern can be interpolated as <b>$1</b>, <b>$2</b> and so on.
<b>TCP-BASED TABLES</b>
This section describes how the table lookups change when
lookups are directed to a TCP-based server. For a descrip-
tion of the TCP client/server lookup protocol, see <a href="tcp_table.5.html"><b>tcp_ta-</b></a>
<a href="tcp_table.5.html"><b>ble</b>(5)</a>. This feature is not available up to and including
Postfix version 2.4.
Each lookup operation uses the entire address once. Thus,
<i>user@domain</i> mail addresses are not broken up into their
<i>user</i> and <i>@domain</i> constituent parts, nor is <i>user+foo</i> broken
up into <i>user</i> and <i>foo</i>.
Results are the same as with indexed file lookups.
<b>BUGS</b>
The table format does not understand quoting conventions.
<b>CONFIGURATION PARAMETERS</b>
The following <a href="postconf.5.html"><b>main.cf</b></a> parameters are especially relevant
to this topic. See the Postfix <a href="postconf.5.html"><b>main.cf</b></a> file for syntax
details and for default values. Use the "<b>postfix reload</b>"
command after a configuration change.
<b><a href="postconf.5.html#virtual_alias_maps">virtual_alias_maps</a></b>
List of virtual aliasing tables.
<b><a href="postconf.5.html#virtual_alias_domains">virtual_alias_domains</a></b>
List of <a href="ADDRESS_CLASS_README.html#virtual_alias_class">virtual alias domains</a>. This uses the same
syntax as the <b><a href="postconf.5.html#mydestination">mydestination</a></b> parameter.
<b><a href="postconf.5.html#propagate_unmatched_extensions">propagate_unmatched_extensions</a></b>
A list of address rewriting or forwarding mecha-
nisms that propagate an address extension from the
original address to the result. Specify zero or
more of <b>canonical</b>, <b>virtual</b>, <b>alias</b>, <b>forward</b>,
<b>include</b>, or <b>generic</b>.
Other parameters of interest:
<b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a></b>
The network interface addresses that this system
receives mail on. You need to stop and start Post-
fix when this parameter changes.
<b><a href="postconf.5.html#mydestination">mydestination</a></b>
List of domains that this mail system considers
local.
<b><a href="postconf.5.html#myorigin">myorigin</a></b>
The domain that is appended to any address that
does not have a domain.
<b><a href="postconf.5.html#owner_request_special">owner_request_special</a></b>
Give special treatment to <b>owner-</b><i>xxx</i> and <i>xxx</i><b>-request</b>
addresses.
<b><a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a></b>
Other interfaces that this machine receives mail on
by way of a proxy agent or network address transla-
tor.
<b>SEE ALSO</b>
<a href="cleanup.8.html">cleanup(8)</a>, canonicalize and enqueue mail
<a href="postmap.1.html">postmap(1)</a>, Postfix lookup table manager
<a href="postconf.5.html">postconf(5)</a>, configuration parameters
<a href="canonical.5.html">canonical(5)</a>, canonical address mapping
<b>README FILES</b>
<a href="ADDRESS_REWRITING_README.html">ADDRESS_REWRITING_README</a>, address rewriting guide
<a href="DATABASE_README.html">DATABASE_README</a>, Postfix lookup table overview
<a href="VIRTUAL_README.html">VIRTUAL_README</a>, domain hosting guide
<b>LICENSE</b>
The Secure Mailer license must be distributed with this
software.
<b>AUTHOR(S)</b>
Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA
VIRTUAL(5)
</pre> </body> </html>
|