1 <!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN" 2 "https://www.w3.org/TR/html4/loose.dtd"> 3 <html> <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 5 <link rel='stylesheet' type='text/css' href='postfix-doc.css'> 6 <title> Postfix manual - virtual(8) </title> 7 </head> <body> <pre> 8 VIRTUAL(8) VIRTUAL(8) 9 10 <b><a name="name">NAME</a></b> 11 virtual - Postfix virtual domain mail delivery agent 12 13 <b><a name="synopsis">SYNOPSIS</a></b> 14 <b>virtual</b> [generic Postfix daemon options] 15 16 <b><a name="description">DESCRIPTION</a></b> 17 The <a href="virtual.8.html"><b>virtual</b>(8)</a> delivery agent is designed for virtual mail hosting ser- 18 vices. Originally based on the Postfix <a href="local.8.html"><b>local</b>(8)</a> delivery agent, this 19 agent looks up recipients with map lookups of their full recipient 20 address, instead of using hard-coded unix password file lookups of the 21 address local part only. 22 23 This delivery agent only delivers mail. Other features such as mail 24 forwarding, out-of-office notifications, etc., must be configured via 25 virtual_alias maps or via similar lookup mechanisms. 26 27 <b><a name="mailbox_location">MAILBOX LOCATION</a></b> 28 The mailbox location is controlled by the <b><a href="postconf.5.html#virtual_mailbox_base">virtual_mailbox_base</a></b> and <b><a href="postconf.5.html#virtual_mailbox_maps">vir</a>-</b> 29 <b><a href="postconf.5.html#virtual_mailbox_maps">tual_mailbox_maps</a></b> configuration parameters (see below). The <b><a href="postconf.5.html#virtual_mailbox_maps">vir-</b> 30 <b>tual_mailbox_maps</a></b> table is indexed by the recipient address as 31 described under TABLE SEARCH ORDER below. 32 33 The mailbox pathname is constructed as follows: 34 35 <b>$<a href="postconf.5.html#virtual_mailbox_base">virtual_mailbox_base</a>/$virtual_mailbox_maps(</b><i>recipient</i><b>)</b> 36 37 where <i>recipient</i> is the full recipient address. 38 39 <b><a name="unix_mailbox_format">UNIX MAILBOX FORMAT</a></b> 40 When the mailbox location does not end in <b>/</b>, the message is delivered 41 in UNIX mailbox format. This format stores multiple messages in one 42 textfile. 43 44 The <a href="virtual.8.html"><b>virtual</b>(8)</a> delivery agent prepends a "<b>From</b> <i>sender time</i><b>_</b><i>stamp</i>" enve- 45 lope header to each message, prepends a <b>Delivered-To:</b> message header 46 with the envelope recipient address, prepends an <b>X-Original-To:</b> header 47 with the recipient address as given to Postfix, prepends a <b>Return-Path:</b> 48 message header with the envelope sender address, prepends a > character 49 to lines beginning with "<b>From</b> ", and appends an empty line. 50 51 The mailbox is locked for exclusive access while delivery is in 52 progress. In case of problems, an attempt is made to truncate the mail- 53 box to its original length. 54 55 <b><a name="qmail_maildir_format">QMAIL MAILDIR FORMAT</a></b> 56 When the mailbox location ends in <b>/</b>, the message is delivered in qmail 57 <b>maildir</b> format. This format stores one message per file. 58 59 The <a href="virtual.8.html"><b>virtual</b>(8)</a> delivery agent prepends a <b>Delivered-To:</b> message header 60 with the final envelope recipient address, prepends an <b>X-Original-To:</b> 61 header with the recipient address as given to Postfix, and prepends a 62 <b>Return-Path:</b> message header with the envelope sender address. 63 64 By definition, <b>maildir</b> format does not require application-level file 65 locking during mail delivery or retrieval. 66 67 <b><a name="mailbox_ownership">MAILBOX OWNERSHIP</a></b> 68 Mailbox ownership is controlled by the <b><a href="postconf.5.html#virtual_uid_maps">virtual_uid_maps</a></b> and <b><a href="postconf.5.html#virtual_gid_maps">vir</a>-</b> 69 <b><a href="postconf.5.html#virtual_gid_maps">tual_gid_maps</a></b> lookup tables, which are indexed with the full recipient 70 address. Each table provides a string with the numerical user and group 71 ID, respectively. 72 73 The <b><a href="postconf.5.html#virtual_minimum_uid">virtual_minimum_uid</a></b> parameter imposes a lower bound on numerical 74 user ID values that may be specified in any <b><a href="postconf.5.html#virtual_uid_maps">virtual_uid_maps</a></b>. 75 76 <b><a name="case_folding">CASE FOLDING</a></b> 77 All delivery decisions are made using the full recipient address, 78 folded to lower case. See also the next section for a few exceptions 79 with optional address extensions. 80 81 <b><a name="table_search_order">TABLE SEARCH ORDER</a></b> 82 Normally, a lookup table is specified as a text file that serves as 83 input to the <a href="postmap.1.html"><b>postmap</b>(1)</a> command. The result, an indexed file in <b>dbm</b> or 84 <b>db</b> format, is used for fast searching by the mail system. 85 86 The search order is as follows. The search stops upon the first suc- 87 cessful lookup. 88 89 <b>o</b> When the recipient has an optional address extension the 90 <i>user+extension (a] domain.tld</i> address is looked up first. 91 92 With Postfix versions before 2.1, the optional address extension 93 is always ignored. 94 95 <b>o</b> The <i>user (a] domain.tld</i> address, without address extension, is 96 looked up next. 97 98 <b>o</b> Finally, the recipient <i>@domain</i> is looked up. 99 100 When the table is provided via other means such as NIS, LDAP or SQL, 101 the same lookups are done as for ordinary indexed files. 102 103 Alternatively, a table can be provided as a regular-expression map 104 where patterns are given as regular expressions. In that case, only the 105 full recipient address is given to the regular-expression map. 106 107 <b><a name="security">SECURITY</a></b> 108 The <a href="virtual.8.html"><b>virtual</b>(8)</a> delivery agent is not security sensitive, provided that 109 the lookup tables with recipient user/group ID information are ade- 110 quately protected. This program is not designed to run chrooted. 111 112 The <a href="virtual.8.html"><b>virtual</b>(8)</a> delivery agent disallows regular expression substitution 113 of $1 etc. in regular expression lookup tables, because that would open 114 a security hole. 115 116 The <a href="virtual.8.html"><b>virtual</b>(8)</a> delivery agent will silently ignore requests to use the 117 <a href="proxymap.8.html"><b>proxymap</b>(8)</a> server. Instead it will open the table directly. Before 118 Postfix version 2.2, the virtual delivery agent will terminate with a 119 fatal error. 120 121 <b><a name="standards">STANDARDS</a></b> 122 <a href="https://tools.ietf.org/html/rfc822">RFC 822</a> (ARPA Internet Text Messages) 123 124 <b><a name="diagnostics">DIAGNOSTICS</a></b> 125 Mail bounces when the recipient has no mailbox or when the recipient is 126 over disk quota. In all other problem cases, mail for an existing 127 recipient is deferred and a warning is logged. 128 129 Problems and transactions are logged to <b>syslogd</b>(8) or <a href="postlogd.8.html"><b>postlogd</b>(8)</a>. 130 Corrupted message files are marked so that the queue manager can move 131 them to the <b>corrupt</b> queue afterwards. 132 133 Depending on the setting of the <b><a href="postconf.5.html#notify_classes">notify_classes</a></b> parameter, the postmas- 134 ter is notified of bounces and of other trouble. 135 136 <b><a name="bugs">BUGS</a></b> 137 This delivery agent supports address extensions in email addresses and 138 in lookup table keys, but does not propagate address extension informa- 139 tion to the result of table lookup. 140 141 Postfix should have lookup tables that can return multiple result 142 attributes. In order to avoid the inconvenience of maintaining three 143 tables, use an LDAP or MYSQL database. 144 145 <b><a name="configuration_parameters">CONFIGURATION PARAMETERS</a></b> 146 Changes to <a href="postconf.5.html"><b>main.cf</b></a> are picked up automatically, as <a href="virtual.8.html"><b>virtual</b>(8)</a> processes 147 run for only a limited amount of time. Use the command "<b>postfix reload</b>" 148 to speed up a change. 149 150 The text below provides only a parameter summary. See <a href="postconf.5.html"><b>postconf</b>(5)</a> for 151 more details including examples. 152 153 <b><a name="mailbox_delivery_controls">MAILBOX DELIVERY CONTROLS</a></b> 154 <b><a href="postconf.5.html#virtual_mailbox_base">virtual_mailbox_base</a> (empty)</b> 155 A prefix that the <a href="virtual.8.html"><b>virtual</b>(8)</a> delivery agent prepends to all 156 pathname results from $<a href="postconf.5.html#virtual_mailbox_maps">virtual_mailbox_maps</a> table lookups. 157 158 <b><a href="postconf.5.html#virtual_mailbox_maps">virtual_mailbox_maps</a> (empty)</b> 159 Optional lookup tables with all valid addresses in the domains 160 that match $<a href="postconf.5.html#virtual_mailbox_domains">virtual_mailbox_domains</a>. 161 162 <b><a href="postconf.5.html#virtual_minimum_uid">virtual_minimum_uid</a> (100)</b> 163 The minimum user ID value that the <a href="virtual.8.html"><b>virtual</b>(8)</a> delivery agent 164 accepts as a result from $<a href="postconf.5.html#virtual_uid_maps">virtual_uid_maps</a> table lookup. 165 166 <b><a href="postconf.5.html#virtual_uid_maps">virtual_uid_maps</a> (empty)</b> 167 Lookup tables with the per-recipient user ID that the <a href="virtual.8.html"><b>virtual</b>(8)</a> 168 delivery agent uses while writing to the recipient's mailbox. 169 170 <b><a href="postconf.5.html#virtual_gid_maps">virtual_gid_maps</a> (empty)</b> 171 Lookup tables with the per-recipient group ID for <a href="virtual.8.html"><b>virtual</b>(8)</a> 172 mailbox delivery. 173 174 Available in Postfix version 2.0 and later: 175 176 <b><a href="postconf.5.html#virtual_mailbox_domains">virtual_mailbox_domains</a> ($<a href="postconf.5.html#virtual_mailbox_maps">virtual_mailbox_maps</a>)</b> 177 Postfix is the final destination for the specified list of 178 domains; mail is delivered via the $<a href="postconf.5.html#virtual_transport">virtual_transport</a> mail 179 delivery transport. 180 181 <b><a href="postconf.5.html#virtual_transport">virtual_transport</a> (virtual)</b> 182 The default mail delivery transport and next-hop destination for 183 final delivery to domains listed with $<a href="postconf.5.html#virtual_mailbox_domains">virtual_mailbox_domains</a>. 184 185 Available in Postfix version 2.5.3 and later: 186 187 <b><a href="postconf.5.html#strict_mailbox_ownership">strict_mailbox_ownership</a> (yes)</b> 188 Defer delivery when a mailbox file is not owned by its recipi- 189 ent. 190 191 <b><a name="locking_controls">LOCKING CONTROLS</a></b> 192 <b><a href="postconf.5.html#virtual_mailbox_lock">virtual_mailbox_lock</a> (see 'postconf -d' output)</b> 193 How to lock a UNIX-style <a href="virtual.8.html"><b>virtual</b>(8)</a> mailbox before attempting 194 delivery. 195 196 <b><a href="postconf.5.html#deliver_lock_attempts">deliver_lock_attempts</a> (20)</b> 197 The maximal number of attempts to acquire an exclusive lock on a 198 mailbox file or <a href="bounce.8.html"><b>bounce</b>(8)</a> logfile. 199 200 <b><a href="postconf.5.html#deliver_lock_delay">deliver_lock_delay</a> (1s)</b> 201 The time between attempts to acquire an exclusive lock on a 202 mailbox file or <a href="bounce.8.html"><b>bounce</b>(8)</a> logfile. 203 204 <b><a href="postconf.5.html#stale_lock_time">stale_lock_time</a> (500s)</b> 205 The time after which a stale exclusive mailbox lockfile is 206 removed. 207 208 <b><a name="resource_and_rate_controls">RESOURCE AND RATE CONTROLS</a></b> 209 <b><a href="postconf.5.html#virtual_mailbox_limit">virtual_mailbox_limit</a> (51200000)</b> 210 The maximal size in bytes of an individual <a href="virtual.8.html"><b>virtual</b>(8)</a> mailbox or 211 maildir file, or zero (no limit). 212 213 Implemented in the <a href="qmgr.8.html">qmgr(8)</a> daemon: 214 215 <b><a href="postconf.5.html#virtual_destination_concurrency_limit">virtual_destination_concurrency_limit</a> ($<a href="postconf.5.html#default_destination_concurrency_limit">default_destination_concur</a>-</b> 216 <b><a href="postconf.5.html#default_destination_concurrency_limit">rency_limit</a>)</b> 217 The maximal number of parallel deliveries to the same destina- 218 tion via the virtual message delivery transport. 219 220 <b><a href="postconf.5.html#virtual_destination_recipient_limit">virtual_destination_recipient_limit</a> ($<a href="postconf.5.html#default_destination_recipient_limit">default_destination_recipi</a>-</b> 221 <b><a href="postconf.5.html#default_destination_recipient_limit">ent_limit</a>)</b> 222 The maximal number of recipients per message for the virtual 223 message delivery transport. 224 225 <b><a name="miscellaneous_controls">MISCELLANEOUS CONTROLS</a></b> 226 <b><a href="postconf.5.html#config_directory">config_directory</a> (see 'postconf -d' output)</b> 227 The default location of the Postfix <a href="postconf.5.html">main.cf</a> and <a href="master.5.html">master.cf</a> con- 228 figuration files. 229 230 <b><a href="postconf.5.html#daemon_timeout">daemon_timeout</a> (18000s)</b> 231 How much time a Postfix daemon process may take to handle a 232 request before it is terminated by a built-in watchdog timer. 233 234 <b><a href="postconf.5.html#delay_logging_resolution_limit">delay_logging_resolution_limit</a> (2)</b> 235 The maximal number of digits after the decimal point when log- 236 ging delay values. 237 238 <b><a href="postconf.5.html#ipc_timeout">ipc_timeout</a> (3600s)</b> 239 The time limit for sending or receiving information over an 240 internal communication channel. 241 242 <b><a href="postconf.5.html#max_idle">max_idle</a> (100s)</b> 243 The maximum amount of time that an idle Postfix daemon process 244 waits for an incoming connection before terminating voluntarily. 245 246 <b><a href="postconf.5.html#max_use">max_use</a> (100)</b> 247 The maximal number of incoming connections that a Postfix daemon 248 process will service before terminating voluntarily. 249 250 <b><a href="postconf.5.html#process_id">process_id</a> (read-only)</b> 251 The process ID of a Postfix command or daemon process. 252 253 <b><a href="postconf.5.html#process_name">process_name</a> (read-only)</b> 254 The process name of a Postfix command or daemon process. 255 256 <b><a href="postconf.5.html#queue_directory">queue_directory</a> (see 'postconf -d' output)</b> 257 The location of the Postfix top-level queue directory. 258 259 <b><a href="postconf.5.html#syslog_facility">syslog_facility</a> (mail)</b> 260 The syslog facility of Postfix logging. 261 262 <b><a href="postconf.5.html#syslog_name">syslog_name</a> (see 'postconf -d' output)</b> 263 A prefix that is prepended to the process name in syslog 264 records, so that, for example, "smtpd" becomes "prefix/smtpd". 265 266 Available in Postfix version 3.0 and later: 267 268 <b><a href="postconf.5.html#virtual_delivery_status_filter">virtual_delivery_status_filter</a> ($<a href="postconf.5.html#default_delivery_status_filter">default_delivery_status_filter</a>)</b> 269 Optional filter for the <a href="virtual.8.html"><b>virtual</b>(8)</a> delivery agent to change the 270 delivery status code or explanatory text of successful or unsuc- 271 cessful deliveries. 272 273 Available in Postfix version 3.3 and later: 274 275 <b><a href="postconf.5.html#enable_original_recipient">enable_original_recipient</a> (yes)</b> 276 Enable support for the original recipient address after an 277 address is rewritten to a different address (for example with 278 aliasing or with canonical mapping). 279 280 <b><a href="postconf.5.html#service_name">service_name</a> (read-only)</b> 281 The <a href="master.5.html">master.cf</a> service name of a Postfix daemon process. 282 283 Available in Postfix 3.5 and later: 284 285 <b><a href="postconf.5.html#info_log_address_format">info_log_address_format</a> (external)</b> 286 The email address form that will be used in non-debug logging 287 (info, warning, etc.). 288 289 <b><a name="see_also">SEE ALSO</a></b> 290 <a href="qmgr.8.html">qmgr(8)</a>, queue manager 291 <a href="bounce.8.html">bounce(8)</a>, delivery status reports 292 <a href="postconf.5.html">postconf(5)</a>, configuration parameters 293 <a href="postlogd.8.html">postlogd(8)</a>, Postfix logging 294 syslogd(8), system logging 295 296 <b><a name="readme_files">README_FILES</a></b> 297 Use "<b>postconf <a href="postconf.5.html#readme_directory">readme_directory</a></b>" or 298 "<b>postconf <a href="postconf.5.html#html_directory">html_directory</a></b>" to locate this information. 299 <a href="VIRTUAL_README.html">VIRTUAL_README</a>, domain hosting howto 300 301 <b><a name="license">LICENSE</a></b> 302 The Secure Mailer license must be distributed with this software. 303 304 <b><a name="history">HISTORY</a></b> 305 This delivery agent was originally based on the Postfix local delivery 306 agent. Modifications mainly consisted of removing code that either was 307 not applicable or that was not safe in this context: aliases, 308 ~user/.forward files, delivery to "|command" or to /file/name. 309 310 The <b>Delivered-To:</b> message header appears in the <b>qmail</b> system by Daniel 311 Bernstein. 312 313 The <b>maildir</b> structure appears in the <b>qmail</b> system by Daniel Bernstein. 314 315 <b>AUTHOR(S)</b> 316 Wietse Venema 317 IBM T.J. Watson Research 318 P.O. Box 704 319 Yorktown Heights, NY 10598, USA 320 321 Wietse Venema 322 Google, Inc. 323 111 8th Avenue 324 New York, NY 10011, USA 325 326 Andrew McNamara 327 andrewm (a] connect.com.au 328 connect.com.au Pty. Ltd. 329 Level 3, 213 Miller St 330 North Sydney 2060, NSW, Australia 331 332 VIRTUAL(8) 333 </pre> </body> </html> 334
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