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