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=utf-8"> 5<title> Postfix manual - smtpd(8) </title> 6</head> <body> <pre> 7SMTPD(8) SMTPD(8) 8 9<b>NAME</b> 10 smtpd - Postfix SMTP server 11 12<b>SYNOPSIS</b> 13 <b>smtpd</b> [generic Postfix daemon options] 14 15 <b>sendmail -bs</b> 16 17<b>DESCRIPTION</b> 18 The SMTP server accepts network connection requests and performs zero 19 or more SMTP transactions per connection. Each received message is 20 piped through the <a href="cleanup.8.html"><b>cleanup</b>(8)</a> daemon, and is placed into the <b>incoming</b> 21 queue as one single queue file. For this mode of operation, the pro- 22 gram expects to be run from the <a href="master.8.html"><b>master</b>(8)</a> process manager. 23 24 Alternatively, the SMTP server be can run in stand-alone mode; this is 25 traditionally obtained with "<b>sendmail -bs</b>". When the SMTP server runs 26 stand-alone with non $<b><a href="postconf.5.html#mail_owner">mail_owner</a></b> privileges, it receives mail even 27 while the mail system is not running, deposits messages directly into 28 the <b>maildrop</b> queue, and disables the SMTP server's access policies. As 29 of Postfix version 2.3, the SMTP server refuses to receive mail from 30 the network when it runs with non $<b><a href="postconf.5.html#mail_owner">mail_owner</a></b> privileges. 31 32 The SMTP server implements a variety of policies for connection 33 requests, and for parameters given to <b>HELO, ETRN, MAIL FROM, VRFY</b> and 34 <b>RCPT TO</b> commands. They are detailed below and in the <a href="postconf.5.html"><b>main.cf</b></a> configura- 35 tion file. 36 37<b>SECURITY</b> 38 The SMTP server is moderately security-sensitive. It talks to SMTP 39 clients and to DNS servers on the network. The SMTP server can be run 40 chrooted at fixed low privilege. 41 42<b>STANDARDS</b> 43 <a href="https://tools.ietf.org/html/rfc821">RFC 821</a> (SMTP protocol) 44 <a href="https://tools.ietf.org/html/rfc1123">RFC 1123</a> (Host requirements) 45 <a href="https://tools.ietf.org/html/rfc1652">RFC 1652</a> (8bit-MIME transport) 46 <a href="https://tools.ietf.org/html/rfc1869">RFC 1869</a> (SMTP service extensions) 47 <a href="https://tools.ietf.org/html/rfc1870">RFC 1870</a> (Message size declaration) 48 <a href="https://tools.ietf.org/html/rfc1985">RFC 1985</a> (ETRN command) 49 <a href="https://tools.ietf.org/html/rfc2034">RFC 2034</a> (SMTP enhanced status codes) 50 <a href="https://tools.ietf.org/html/rfc2554">RFC 2554</a> (AUTH command) 51 <a href="https://tools.ietf.org/html/rfc2821">RFC 2821</a> (SMTP protocol) 52 <a href="https://tools.ietf.org/html/rfc2920">RFC 2920</a> (SMTP pipelining) 53 <a href="https://tools.ietf.org/html/rfc3030">RFC 3030</a> (CHUNKING without BINARYMIME) 54 <a href="https://tools.ietf.org/html/rfc3207">RFC 3207</a> (STARTTLS command) 55 <a href="https://tools.ietf.org/html/rfc3461">RFC 3461</a> (SMTP DSN extension) 56 <a href="https://tools.ietf.org/html/rfc3463">RFC 3463</a> (Enhanced status codes) 57 <a href="https://tools.ietf.org/html/rfc3848">RFC 3848</a> (ESMTP transmission types) 58 <a href="https://tools.ietf.org/html/rfc4409">RFC 4409</a> (Message submission) 59 <a href="https://tools.ietf.org/html/rfc4954">RFC 4954</a> (AUTH command) 60 <a href="https://tools.ietf.org/html/rfc5321">RFC 5321</a> (SMTP protocol) 61 <a href="https://tools.ietf.org/html/rfc6531">RFC 6531</a> (Internationalized SMTP) 62 <a href="https://tools.ietf.org/html/rfc6533">RFC 6533</a> (Internationalized Delivery Status Notifications) 63 <a href="https://tools.ietf.org/html/rfc7505">RFC 7505</a> ("Null MX" No Service Resource Record) 64 65<b>DIAGNOSTICS</b> 66 Problems and transactions are logged to <b>syslogd</b>(8) or <a href="postlogd.8.html"><b>postlogd</b>(8)</a>. 67 68 Depending on the setting of the <b><a href="postconf.5.html#notify_classes">notify_classes</a></b> parameter, the postmas- 69 ter is notified of bounces, protocol problems, policy violations, and 70 of other trouble. 71 72<b>CONFIGURATION PARAMETERS</b> 73 Changes to <a href="postconf.5.html"><b>main.cf</b></a> are picked up automatically, as <a href="smtpd.8.html"><b>smtpd</b>(8)</a> processes 74 run for only a limited amount of time. Use the command "<b>postfix reload</b>" 75 to speed up a change. 76 77 The text below provides only a parameter summary. See <a href="postconf.5.html"><b>postconf</b>(5)</a> for 78 more details including examples. 79 80<b>COMPATIBILITY CONTROLS</b> 81 The following parameters work around implementation errors in other 82 software, and/or allow you to override standards in order to prevent 83 undesirable use. 84 85 <b><a href="postconf.5.html#broken_sasl_auth_clients">broken_sasl_auth_clients</a> (no)</b> 86 Enable interoperability with remote SMTP clients that implement 87 an obsolete version of the AUTH command (<a href="https://tools.ietf.org/html/rfc4954">RFC 4954</a>). 88 89 <b><a href="postconf.5.html#disable_vrfy_command">disable_vrfy_command</a> (no)</b> 90 Disable the SMTP VRFY command. 91 92 <b><a href="postconf.5.html#smtpd_noop_commands">smtpd_noop_commands</a> (empty)</b> 93 List of commands that the Postfix SMTP server replies to with 94 "250 Ok", without doing any syntax checks and without changing 95 state. 96 97 <b><a href="postconf.5.html#strict_rfc821_envelopes">strict_rfc821_envelopes</a> (no)</b> 98 Require that addresses received in SMTP MAIL FROM and RCPT TO 99 commands are enclosed with <>, and that those addresses do not 100 contain <a href="https://tools.ietf.org/html/rfc822">RFC 822</a> style comments or phrases. 101 102 Available in Postfix version 2.1 and later: 103 104 <b><a href="postconf.5.html#smtpd_reject_unlisted_sender">smtpd_reject_unlisted_sender</a> (no)</b> 105 Request that the Postfix SMTP server rejects mail from unknown 106 sender addresses, even when no explicit <a href="postconf.5.html#reject_unlisted_sender">reject_unlisted_sender</a> 107 access restriction is specified. 108 109 <b><a href="postconf.5.html#smtpd_sasl_exceptions_networks">smtpd_sasl_exceptions_networks</a> (empty)</b> 110 What remote SMTP clients the Postfix SMTP server will not offer 111 AUTH support to. 112 113 Available in Postfix version 2.2 and later: 114 115 <b><a href="postconf.5.html#smtpd_discard_ehlo_keyword_address_maps">smtpd_discard_ehlo_keyword_address_maps</a> (empty)</b> 116 Lookup tables, indexed by the remote SMTP client address, with 117 case insensitive lists of EHLO keywords (pipelining, starttls, 118 auth, etc.) that the Postfix SMTP server will not send in the 119 EHLO response to a remote SMTP client. 120 121 <b><a href="postconf.5.html#smtpd_discard_ehlo_keywords">smtpd_discard_ehlo_keywords</a> (empty)</b> 122 A case insensitive list of EHLO keywords (pipelining, starttls, 123 auth, etc.) that the Postfix SMTP server will not send in the 124 EHLO response to a remote SMTP client. 125 126 <b><a href="postconf.5.html#smtpd_delay_open_until_valid_rcpt">smtpd_delay_open_until_valid_rcpt</a> (yes)</b> 127 Postpone the start of an SMTP mail transaction until a valid 128 RCPT TO command is received. 129 130 Available in Postfix version 2.3 and later: 131 132 <b><a href="postconf.5.html#smtpd_tls_always_issue_session_ids">smtpd_tls_always_issue_session_ids</a> (yes)</b> 133 Force the Postfix SMTP server to issue a TLS session id, even 134 when TLS session caching is turned off (<a href="postconf.5.html#smtpd_tls_session_cache_database">smtpd_tls_ses</a>- 135 <a href="postconf.5.html#smtpd_tls_session_cache_database">sion_cache_database</a> is empty). 136 137 Available in Postfix version 2.6 and later: 138 139 <b><a href="postconf.5.html#tcp_windowsize">tcp_windowsize</a> (0)</b> 140 An optional workaround for routers that break TCP window scal- 141 ing. 142 143 Available in Postfix version 2.7 and later: 144 145 <b><a href="postconf.5.html#smtpd_command_filter">smtpd_command_filter</a> (empty)</b> 146 A mechanism to transform commands from remote SMTP clients. 147 148 Available in Postfix version 2.9 - 3.6: 149 150 <b><a href="postconf.5.html#smtpd_per_record_deadline">smtpd_per_record_deadline</a> (normal: no, overload: yes)</b> 151 Change the behavior of the <a href="postconf.5.html#smtpd_timeout">smtpd_timeout</a> and <a href="postconf.5.html#smtpd_starttls_timeout">smtpd_start</a>- 152 <a href="postconf.5.html#smtpd_starttls_timeout">tls_timeout</a> time limits, from a time limit per read or write 153 system call, to a time limit to send or receive a complete 154 record (an SMTP command line, SMTP response line, SMTP message 155 content line, or TLS protocol message). 156 157 Available in Postfix version 3.0 and later: 158 159 <b><a href="postconf.5.html#smtpd_dns_reply_filter">smtpd_dns_reply_filter</a> (empty)</b> 160 Optional filter for Postfix SMTP server DNS lookup results. 161 162 Available in Postfix version 3.6 and later: 163 164 <b><a href="postconf.5.html#smtpd_relay_before_recipient_restrictions">smtpd_relay_before_recipient_restrictions</a> (see 'postconf -d' output)</b> 165 Evaluate <a href="postconf.5.html#smtpd_relay_restrictions">smtpd_relay_restrictions</a> before <a href="postconf.5.html#smtpd_recipient_restrictions">smtpd_recipi</a>- 166 <a href="postconf.5.html#smtpd_recipient_restrictions">ent_restrictions</a>. 167 168 <b><a href="postconf.5.html#known_tcp_ports">known_tcp_ports</a> (lmtp=24, smtp=25, smtps=submissions=465, submis-</b> 169 <b>sion=587)</b> 170 Optional setting that avoids lookups in the <b>services</b>(5) data- 171 base. 172 173 Available in Postfix version 3.7 and later: 174 175 <b><a href="postconf.5.html#smtpd_per_request_deadline">smtpd_per_request_deadline</a> (normal: no, overload: yes)</b> 176 Change the behavior of the <a href="postconf.5.html#smtpd_timeout">smtpd_timeout</a> and <a href="postconf.5.html#smtpd_starttls_timeout">smtpd_start</a>- 177 <a href="postconf.5.html#smtpd_starttls_timeout">tls_timeout</a> time limits, from a time limit per plaintext or TLS 178 read or write call, to a combined time limit for receiving a 179 complete SMTP request and for sending a complete SMTP response. 180 181 <b><a href="postconf.5.html#smtpd_min_data_rate">smtpd_min_data_rate</a> (500)</b> 182 The minimum plaintext data transfer rate in bytes/second for 183 DATA and BDAT requests, when deadlines are enabled with 184 <a href="postconf.5.html#smtpd_per_request_deadline">smtpd_per_request_deadline</a>. 185 186<b>ADDRESS REWRITING CONTROLS</b> 187 See the <a href="ADDRESS_REWRITING_README.html">ADDRESS_REWRITING_README</a> document for a detailed discussion of 188 Postfix address rewriting. 189 190 <b><a href="postconf.5.html#receive_override_options">receive_override_options</a> (empty)</b> 191 Enable or disable recipient validation, built-in content filter- 192 ing, or address mapping. 193 194 Available in Postfix version 2.2 and later: 195 196 <b><a href="postconf.5.html#local_header_rewrite_clients">local_header_rewrite_clients</a> (<a href="postconf.5.html#permit_inet_interfaces">permit_inet_interfaces</a>)</b> 197 Rewrite message header addresses in mail from these clients and 198 update incomplete addresses with the domain name in $<a href="postconf.5.html#myorigin">myorigin</a> or 199 $<a href="postconf.5.html#mydomain">mydomain</a>; either don't rewrite message headers from other 200 clients at all, or rewrite message headers and update incomplete 201 addresses with the domain specified in the <a href="postconf.5.html#remote_header_rewrite_domain">remote_header_re</a>- 202 <a href="postconf.5.html#remote_header_rewrite_domain">write_domain</a> parameter. 203 204<b>BEFORE-SMTPD PROXY AGENT</b> 205 Available in Postfix version 2.10 and later: 206 207 <b><a href="postconf.5.html#smtpd_upstream_proxy_protocol">smtpd_upstream_proxy_protocol</a> (empty)</b> 208 The name of the proxy protocol used by an optional before-smtpd 209 proxy agent. 210 211 <b><a href="postconf.5.html#smtpd_upstream_proxy_timeout">smtpd_upstream_proxy_timeout</a> (5s)</b> 212 The time limit for the proxy protocol specified with the 213 <a href="postconf.5.html#smtpd_upstream_proxy_protocol">smtpd_upstream_proxy_protocol</a> parameter. 214 215<b>AFTER QUEUE EXTERNAL CONTENT INSPECTION CONTROLS</b> 216 As of version 1.0, Postfix can be configured to send new mail to an 217 external content filter AFTER the mail is queued. This content filter 218 is expected to inject mail back into a (Postfix or other) MTA for fur- 219 ther delivery. See the <a href="FILTER_README.html">FILTER_README</a> document for details. 220 221 <b><a href="postconf.5.html#content_filter">content_filter</a> (empty)</b> 222 After the message is queued, send the entire message to the 223 specified <i>transport:destination</i>. 224 225<b>BEFORE QUEUE EXTERNAL CONTENT INSPECTION CONTROLS</b> 226 As of version 2.1, the Postfix SMTP server can be configured to send 227 incoming mail to a real-time SMTP-based content filter BEFORE mail is 228 queued. This content filter is expected to inject mail back into Post- 229 fix. See the <a href="SMTPD_PROXY_README.html">SMTPD_PROXY_README</a> document for details on how to config- 230 ure and operate this feature. 231 232 <b><a href="postconf.5.html#smtpd_proxy_filter">smtpd_proxy_filter</a> (empty)</b> 233 The hostname and TCP port of the mail filtering proxy server. 234 235 <b><a href="postconf.5.html#smtpd_proxy_ehlo">smtpd_proxy_ehlo</a> ($<a href="postconf.5.html#myhostname">myhostname</a>)</b> 236 How the Postfix SMTP server announces itself to the proxy fil- 237 ter. 238 239 <b><a href="postconf.5.html#smtpd_proxy_options">smtpd_proxy_options</a> (empty)</b> 240 List of options that control how the Postfix SMTP server commu- 241 nicates with a before-queue content filter. 242 243 <b><a href="postconf.5.html#smtpd_proxy_timeout">smtpd_proxy_timeout</a> (100s)</b> 244 The time limit for connecting to a proxy filter and for sending 245 or receiving information. 246 247<b>BEFORE QUEUE MILTER CONTROLS</b> 248 As of version 2.3, Postfix supports the Sendmail version 8 Milter (mail 249 filter) protocol. These content filters run outside Postfix. They can 250 inspect the SMTP command stream and the message content, and can 251 request modifications before mail is queued. For details see the <a href="MILTER_README.html">MIL</a>- 252 <a href="MILTER_README.html">TER_README</a> document. 253 254 <b><a href="postconf.5.html#smtpd_milters">smtpd_milters</a> (empty)</b> 255 A list of Milter (mail filter) applications for new mail that 256 arrives via the Postfix <a href="smtpd.8.html"><b>smtpd</b>(8)</a> server. 257 258 <b><a href="postconf.5.html#milter_protocol">milter_protocol</a> (6)</b> 259 The mail filter protocol version and optional protocol exten- 260 sions for communication with a Milter application; prior to 261 Postfix 2.6 the default protocol is 2. 262 263 <b><a href="postconf.5.html#milter_default_action">milter_default_action</a> (tempfail)</b> 264 The default action when a Milter (mail filter) response is 265 unavailable (for example, bad Postfix configuration or Milter 266 failure). 267 268 <b><a href="postconf.5.html#milter_macro_daemon_name">milter_macro_daemon_name</a> ($<a href="postconf.5.html#myhostname">myhostname</a>)</b> 269 The {daemon_name} macro value for Milter (mail filter) applica- 270 tions. 271 272 <b><a href="postconf.5.html#milter_macro_v">milter_macro_v</a> ($<a href="postconf.5.html#mail_name">mail_name</a> $<a href="postconf.5.html#mail_version">mail_version</a>)</b> 273 The {v} macro value for Milter (mail filter) applications. 274 275 <b><a href="postconf.5.html#milter_connect_timeout">milter_connect_timeout</a> (30s)</b> 276 The time limit for connecting to a Milter (mail filter) applica- 277 tion, and for negotiating protocol options. 278 279 <b><a href="postconf.5.html#milter_command_timeout">milter_command_timeout</a> (30s)</b> 280 The time limit for sending an SMTP command to a Milter (mail 281 filter) application, and for receiving the response. 282 283 <b><a href="postconf.5.html#milter_content_timeout">milter_content_timeout</a> (300s)</b> 284 The time limit for sending message content to a Milter (mail 285 filter) application, and for receiving the response. 286 287 <b><a href="postconf.5.html#milter_connect_macros">milter_connect_macros</a> (see 'postconf -d' output)</b> 288 The macros that are sent to Milter (mail filter) applications 289 after completion of an SMTP connection. 290 291 <b><a href="postconf.5.html#milter_helo_macros">milter_helo_macros</a> (see 'postconf -d' output)</b> 292 The macros that are sent to Milter (mail filter) applications 293 after the SMTP HELO or EHLO command. 294 295 <b><a href="postconf.5.html#milter_mail_macros">milter_mail_macros</a> (see 'postconf -d' output)</b> 296 The macros that are sent to Milter (mail filter) applications 297 after the SMTP MAIL FROM command. 298 299 <b><a href="postconf.5.html#milter_rcpt_macros">milter_rcpt_macros</a> (see 'postconf -d' output)</b> 300 The macros that are sent to Milter (mail filter) applications 301 after the SMTP RCPT TO command. 302 303 <b><a href="postconf.5.html#milter_data_macros">milter_data_macros</a> (see 'postconf -d' output)</b> 304 The macros that are sent to version 4 or higher Milter (mail 305 filter) applications after the SMTP DATA command. 306 307 <b><a href="postconf.5.html#milter_unknown_command_macros">milter_unknown_command_macros</a> (see 'postconf -d' output)</b> 308 The macros that are sent to version 3 or higher Milter (mail 309 filter) applications after an unknown SMTP command. 310 311 <b><a href="postconf.5.html#milter_end_of_header_macros">milter_end_of_header_macros</a> (see 'postconf -d' output)</b> 312 The macros that are sent to Milter (mail filter) applications 313 after the end of the message header. 314 315 <b><a href="postconf.5.html#milter_end_of_data_macros">milter_end_of_data_macros</a> (see 'postconf -d' output)</b> 316 The macros that are sent to Milter (mail filter) applications 317 after the message end-of-data. 318 319 Available in Postfix version 3.1 and later: 320 321 <b><a href="postconf.5.html#milter_macro_defaults">milter_macro_defaults</a> (empty)</b> 322 Optional list of <i>name=value</i> pairs that specify default values 323 for arbitrary macros that Postfix may send to Milter applica- 324 tions. 325 326 Available in Postfix version 3.2 and later: 327 328 <b><a href="postconf.5.html#smtpd_milter_maps">smtpd_milter_maps</a> (empty)</b> 329 Lookup tables with Milter settings per remote SMTP client IP 330 address. 331 332<b>GENERAL CONTENT INSPECTION CONTROLS</b> 333 The following parameters are applicable for both built-in and external 334 content filters. 335 336 Available in Postfix version 2.1 and later: 337 338 <b><a href="postconf.5.html#receive_override_options">receive_override_options</a> (empty)</b> 339 Enable or disable recipient validation, built-in content filter- 340 ing, or address mapping. 341 342<b>EXTERNAL CONTENT INSPECTION CONTROLS</b> 343 The following parameters are applicable for both before-queue and 344 after-queue content filtering. 345 346 Available in Postfix version 2.1 and later: 347 348 <b><a href="postconf.5.html#smtpd_authorized_xforward_hosts">smtpd_authorized_xforward_hosts</a> (empty)</b> 349 What remote SMTP clients are allowed to use the XFORWARD fea- 350 ture. 351 352<b>SASL AUTHENTICATION CONTROLS</b> 353 Postfix SASL support (<a href="https://tools.ietf.org/html/rfc4954">RFC 4954</a>) can be used to authenticate remote SMTP 354 clients to the Postfix SMTP server, and to authenticate the Postfix 355 SMTP client to a remote SMTP server. See the <a href="SASL_README.html">SASL_README</a> document for 356 details. 357 358 <b><a href="postconf.5.html#broken_sasl_auth_clients">broken_sasl_auth_clients</a> (no)</b> 359 Enable interoperability with remote SMTP clients that implement 360 an obsolete version of the AUTH command (<a href="https://tools.ietf.org/html/rfc4954">RFC 4954</a>). 361 362 <b><a href="postconf.5.html#smtpd_sasl_auth_enable">smtpd_sasl_auth_enable</a> (no)</b> 363 Enable SASL authentication in the Postfix SMTP server. 364 365 <b><a href="postconf.5.html#smtpd_sasl_local_domain">smtpd_sasl_local_domain</a> (empty)</b> 366 The name of the Postfix SMTP server's local SASL authentication 367 realm. 368 369 <b><a href="postconf.5.html#smtpd_sasl_security_options">smtpd_sasl_security_options</a> (noanonymous)</b> 370 Postfix SMTP server SASL security options; as of Postfix 2.3 the 371 list of available features depends on the SASL server implemen- 372 tation that is selected with <b><a href="postconf.5.html#smtpd_sasl_type">smtpd_sasl_type</a></b>. 373 374 <b><a href="postconf.5.html#smtpd_sender_login_maps">smtpd_sender_login_maps</a> (empty)</b> 375 Optional lookup table with the SASL login names that own the 376 sender (MAIL FROM) addresses. 377 378 Available in Postfix version 2.1 and later: 379 380 <b><a href="postconf.5.html#smtpd_sasl_exceptions_networks">smtpd_sasl_exceptions_networks</a> (empty)</b> 381 What remote SMTP clients the Postfix SMTP server will not offer 382 AUTH support to. 383 384 Available in Postfix version 2.1 and 2.2: 385 386 <b><a href="postconf.5.html#smtpd_sasl_application_name">smtpd_sasl_application_name</a> (smtpd)</b> 387 The application name that the Postfix SMTP server uses for SASL 388 server initialization. 389 390 Available in Postfix version 2.3 and later: 391 392 <b><a href="postconf.5.html#smtpd_sasl_authenticated_header">smtpd_sasl_authenticated_header</a> (no)</b> 393 Report the SASL authenticated user name in the <a href="smtpd.8.html"><b>smtpd</b>(8)</a> Received 394 message header. 395 396 <b><a href="postconf.5.html#smtpd_sasl_path">smtpd_sasl_path</a> (smtpd)</b> 397 Implementation-specific information that the Postfix SMTP server 398 passes through to the SASL plug-in implementation that is 399 selected with <b><a href="postconf.5.html#smtpd_sasl_type">smtpd_sasl_type</a></b>. 400 401 <b><a href="postconf.5.html#smtpd_sasl_type">smtpd_sasl_type</a> (cyrus)</b> 402 The SASL plug-in type that the Postfix SMTP server should use 403 for authentication. 404 405 Available in Postfix version 2.5 and later: 406 407 <b><a href="postconf.5.html#cyrus_sasl_config_path">cyrus_sasl_config_path</a> (empty)</b> 408 Search path for Cyrus SASL application configuration files, cur- 409 rently used only to locate the $<a href="postconf.5.html#smtpd_sasl_path">smtpd_sasl_path</a>.conf file. 410 411 Available in Postfix version 2.11 and later: 412 413 <b><a href="postconf.5.html#smtpd_sasl_service">smtpd_sasl_service</a> (smtp)</b> 414 The service name that is passed to the SASL plug-in that is 415 selected with <b><a href="postconf.5.html#smtpd_sasl_type">smtpd_sasl_type</a></b> and <b><a href="postconf.5.html#smtpd_sasl_path">smtpd_sasl_path</a></b>. 416 417 Available in Postfix version 3.4 and later: 418 419 <b><a href="postconf.5.html#smtpd_sasl_response_limit">smtpd_sasl_response_limit</a> (12288)</b> 420 The maximum length of a SASL client's response to a server chal- 421 lenge. 422 423 Available in Postfix 3.6 and later: 424 425 <b><a href="postconf.5.html#smtpd_sasl_mechanism_filter">smtpd_sasl_mechanism_filter</a> (!external, <a href="DATABASE_README.html#types">static</a>:rest)</b> 426 If non-empty, a filter for the SASL mechanism names that the 427 Postfix SMTP server will announce in the EHLO response. 428 429<b>STARTTLS SUPPORT CONTROLS</b> 430 Detailed information about STARTTLS configuration may be found in the 431 <a href="TLS_README.html">TLS_README</a> document. 432 433 <b><a href="postconf.5.html#smtpd_tls_security_level">smtpd_tls_security_level</a> (empty)</b> 434 The SMTP TLS security level for the Postfix SMTP server; when a 435 non-empty value is specified, this overrides the obsolete param- 436 eters <a href="postconf.5.html#smtpd_use_tls">smtpd_use_tls</a> and <a href="postconf.5.html#smtpd_enforce_tls">smtpd_enforce_tls</a>. 437 438 <b><a href="postconf.5.html#smtpd_sasl_tls_security_options">smtpd_sasl_tls_security_options</a> ($<a href="postconf.5.html#smtpd_sasl_security_options">smtpd_sasl_security_options</a>)</b> 439 The SASL authentication security options that the Postfix SMTP 440 server uses for TLS encrypted SMTP sessions. 441 442 <b><a href="postconf.5.html#smtpd_starttls_timeout">smtpd_starttls_timeout</a> (see 'postconf -d' output)</b> 443 The time limit for Postfix SMTP server write and read operations 444 during TLS startup and shutdown handshake procedures. 445 446 <b><a href="postconf.5.html#smtpd_tls_CAfile">smtpd_tls_CAfile</a> (empty)</b> 447 A file containing (PEM format) CA certificates of root CAs 448 trusted to sign either remote SMTP client certificates or inter- 449 mediate CA certificates. 450 451 <b><a href="postconf.5.html#smtpd_tls_CApath">smtpd_tls_CApath</a> (empty)</b> 452 A directory containing (PEM format) CA certificates of root CAs 453 trusted to sign either remote SMTP client certificates or inter- 454 mediate CA certificates. 455 456 <b><a href="postconf.5.html#smtpd_tls_always_issue_session_ids">smtpd_tls_always_issue_session_ids</a> (yes)</b> 457 Force the Postfix SMTP server to issue a TLS session id, even 458 when TLS session caching is turned off (<a href="postconf.5.html#smtpd_tls_session_cache_database">smtpd_tls_ses</a>- 459 <a href="postconf.5.html#smtpd_tls_session_cache_database">sion_cache_database</a> is empty). 460 461 <b><a href="postconf.5.html#smtpd_tls_ask_ccert">smtpd_tls_ask_ccert</a> (no)</b> 462 Ask a remote SMTP client for a client certificate. 463 464 <b><a href="postconf.5.html#smtpd_tls_auth_only">smtpd_tls_auth_only</a> (no)</b> 465 When TLS encryption is optional in the Postfix SMTP server, do 466 not announce or accept SASL authentication over unencrypted con- 467 nections. 468 469 <b><a href="postconf.5.html#smtpd_tls_ccert_verifydepth">smtpd_tls_ccert_verifydepth</a> (9)</b> 470 The verification depth for remote SMTP client certificates. 471 472 <b><a href="postconf.5.html#smtpd_tls_cert_file">smtpd_tls_cert_file</a> (empty)</b> 473 File with the Postfix SMTP server RSA certificate in PEM format. 474 475 <b><a href="postconf.5.html#smtpd_tls_exclude_ciphers">smtpd_tls_exclude_ciphers</a> (empty)</b> 476 List of ciphers or cipher types to exclude from the SMTP server 477 cipher list at all TLS security levels. 478 479 <b><a href="postconf.5.html#smtpd_tls_dcert_file">smtpd_tls_dcert_file</a> (empty)</b> 480 File with the Postfix SMTP server DSA certificate in PEM format. 481 482 <b><a href="postconf.5.html#smtpd_tls_dh1024_param_file">smtpd_tls_dh1024_param_file</a> (empty)</b> 483 File with DH parameters that the Postfix SMTP server should use 484 with non-export EDH ciphers. 485 486 <b><a href="postconf.5.html#smtpd_tls_dh512_param_file">smtpd_tls_dh512_param_file</a> (empty)</b> 487 File with DH parameters that the Postfix SMTP server should use 488 with export-grade EDH ciphers. 489 490 <b><a href="postconf.5.html#smtpd_tls_dkey_file">smtpd_tls_dkey_file</a> ($<a href="postconf.5.html#smtpd_tls_dcert_file">smtpd_tls_dcert_file</a>)</b> 491 File with the Postfix SMTP server DSA private key in PEM format. 492 493 <b><a href="postconf.5.html#smtpd_tls_key_file">smtpd_tls_key_file</a> ($<a href="postconf.5.html#smtpd_tls_cert_file">smtpd_tls_cert_file</a>)</b> 494 File with the Postfix SMTP server RSA private key in PEM format. 495 496 <b><a href="postconf.5.html#smtpd_tls_loglevel">smtpd_tls_loglevel</a> (0)</b> 497 Enable additional Postfix SMTP server logging of TLS activity. 498 499 <b><a href="postconf.5.html#smtpd_tls_mandatory_ciphers">smtpd_tls_mandatory_ciphers</a> (medium)</b> 500 The minimum TLS cipher grade that the Postfix SMTP server will 501 use with mandatory TLS encryption. 502 503 <b><a href="postconf.5.html#smtpd_tls_mandatory_exclude_ciphers">smtpd_tls_mandatory_exclude_ciphers</a> (empty)</b> 504 Additional list of ciphers or cipher types to exclude from the 505 Postfix SMTP server cipher list at mandatory TLS security lev- 506 els. 507 508 <b><a href="postconf.5.html#smtpd_tls_mandatory_protocols">smtpd_tls_mandatory_protocols</a> (see 'postconf -d' output)</b> 509 TLS protocols accepted by the Postfix SMTP server with mandatory 510 TLS encryption. 511 512 <b><a href="postconf.5.html#smtpd_tls_received_header">smtpd_tls_received_header</a> (no)</b> 513 Request that the Postfix SMTP server produces Received: message 514 headers that include information about the protocol and cipher 515 used, as well as the remote SMTP client CommonName and client 516 certificate issuer CommonName. 517 518 <b><a href="postconf.5.html#smtpd_tls_req_ccert">smtpd_tls_req_ccert</a> (no)</b> 519 With mandatory TLS encryption, require a trusted remote SMTP 520 client certificate in order to allow TLS connections to proceed. 521 522 <b><a href="postconf.5.html#smtpd_tls_wrappermode">smtpd_tls_wrappermode</a> (no)</b> 523 Run the Postfix SMTP server in the non-standard "wrapper" mode, 524 instead of using the STARTTLS command. 525 526 <b><a href="postconf.5.html#tls_daemon_random_bytes">tls_daemon_random_bytes</a> (32)</b> 527 The number of pseudo-random bytes that an <a href="smtp.8.html"><b>smtp</b>(8)</a> or <a href="smtpd.8.html"><b>smtpd</b>(8)</a> 528 process requests from the <a href="tlsmgr.8.html"><b>tlsmgr</b>(8)</a> server in order to seed its 529 internal pseudo random number generator (PRNG). 530 531 <b><a href="postconf.5.html#tls_high_cipherlist">tls_high_cipherlist</a> (see 'postconf -d' output)</b> 532 The OpenSSL cipherlist for "high" grade ciphers. 533 534 <b><a href="postconf.5.html#tls_medium_cipherlist">tls_medium_cipherlist</a> (see 'postconf -d' output)</b> 535 The OpenSSL cipherlist for "medium" or higher grade ciphers. 536 537 <b><a href="postconf.5.html#tls_low_cipherlist">tls_low_cipherlist</a> (see 'postconf -d' output)</b> 538 The OpenSSL cipherlist for "low" or higher grade ciphers. 539 540 <b><a href="postconf.5.html#tls_export_cipherlist">tls_export_cipherlist</a> (see 'postconf -d' output)</b> 541 The OpenSSL cipherlist for "export" or higher grade ciphers. 542 543 <b><a href="postconf.5.html#tls_null_cipherlist">tls_null_cipherlist</a> (eNULL:!aNULL)</b> 544 The OpenSSL cipherlist for "NULL" grade ciphers that provide 545 authentication without encryption. 546 547 Available in Postfix version 2.5 and later: 548 549 <b><a href="postconf.5.html#smtpd_tls_fingerprint_digest">smtpd_tls_fingerprint_digest</a> (see 'postconf -d' output)</b> 550 The message digest algorithm to construct remote SMTP 551 client-certificate fingerprints or public key fingerprints 552 (Postfix 2.9 and later) for <b><a href="postconf.5.html#check_ccert_access">check_ccert_access</a></b> and <b>per-</b> 553 <b>mit_tls_clientcerts</b>. 554 555 Available in Postfix version 2.6 and later: 556 557 <b><a href="postconf.5.html#smtpd_tls_protocols">smtpd_tls_protocols</a> (see postconf -d output)</b> 558 TLS protocols accepted by the Postfix SMTP server with oppor- 559 tunistic TLS encryption. 560 561 <b><a href="postconf.5.html#smtpd_tls_ciphers">smtpd_tls_ciphers</a> (medium)</b> 562 The minimum TLS cipher grade that the Postfix SMTP server will 563 use with opportunistic TLS encryption. 564 565 <b><a href="postconf.5.html#smtpd_tls_eccert_file">smtpd_tls_eccert_file</a> (empty)</b> 566 File with the Postfix SMTP server ECDSA certificate in PEM for- 567 mat. 568 569 <b><a href="postconf.5.html#smtpd_tls_eckey_file">smtpd_tls_eckey_file</a> ($<a href="postconf.5.html#smtpd_tls_eccert_file">smtpd_tls_eccert_file</a>)</b> 570 File with the Postfix SMTP server ECDSA private key in PEM for- 571 mat. 572 573 <b><a href="postconf.5.html#smtpd_tls_eecdh_grade">smtpd_tls_eecdh_grade</a> (see 'postconf -d' output)</b> 574 The Postfix SMTP server security grade for ephemeral ellip- 575 tic-curve Diffie-Hellman (EECDH) key exchange. 576 577 <b><a href="postconf.5.html#tls_eecdh_strong_curve">tls_eecdh_strong_curve</a> (prime256v1)</b> 578 The elliptic curve used by the Postfix SMTP server for sensibly 579 strong ephemeral ECDH key exchange. 580 581 <b><a href="postconf.5.html#tls_eecdh_ultra_curve">tls_eecdh_ultra_curve</a> (secp384r1)</b> 582 The elliptic curve used by the Postfix SMTP server for maximally 583 strong ephemeral ECDH key exchange. 584 585 Available in Postfix version 2.8 and later: 586 587 <b><a href="postconf.5.html#tls_preempt_cipherlist">tls_preempt_cipherlist</a> (no)</b> 588 With SSLv3 and later, use the Postfix SMTP server's cipher pref- 589 erence order instead of the remote client's cipher preference 590 order. 591 592 <b><a href="postconf.5.html#tls_disable_workarounds">tls_disable_workarounds</a> (see 'postconf -d' output)</b> 593 List or bit-mask of OpenSSL bug work-arounds to disable. 594 595 Available in Postfix version 2.11 and later: 596 597 <b><a href="postconf.5.html#tlsmgr_service_name">tlsmgr_service_name</a> (tlsmgr)</b> 598 The name of the <a href="tlsmgr.8.html"><b>tlsmgr</b>(8)</a> service entry in <a href="master.5.html">master.cf</a>. 599 600 Available in Postfix version 3.0 and later: 601 602 <b><a href="postconf.5.html#tls_session_ticket_cipher">tls_session_ticket_cipher</a> (Postfix</b> ><b>= 3.0: aes-256-cbc, Postfix</b> < <b>3.0:</b> 603 <b>aes-128-cbc)</b> 604 Algorithm used to encrypt <a href="https://tools.ietf.org/html/rfc5077">RFC5077</a> TLS session tickets. 605 606 Available in Postfix version 3.2 and later: 607 608 <b><a href="postconf.5.html#tls_eecdh_auto_curves">tls_eecdh_auto_curves</a> (see 'postconf -d' output)</b> 609 The prioritized list of elliptic curves supported by the Postfix 610 SMTP client and server. 611 612 Available in Postfix version 3.4 and later: 613 614 <b><a href="postconf.5.html#smtpd_tls_chain_files">smtpd_tls_chain_files</a> (empty)</b> 615 List of one or more PEM files, each holding one or more private 616 keys directly followed by a corresponding certificate chain. 617 618 <b><a href="postconf.5.html#tls_server_sni_maps">tls_server_sni_maps</a> (empty)</b> 619 Optional lookup tables that map names received from remote SMTP 620 clients via the TLS Server Name Indication (SNI) extension to 621 the appropriate keys and certificate chains. 622 623 Available in Postfix 3.5, 3.4.6, 3.3.5, 3.2.10, 3.1.13 and later: 624 625 <b><a href="postconf.5.html#tls_fast_shutdown_enable">tls_fast_shutdown_enable</a> (yes)</b> 626 A workaround for implementations that hang Postfix while shut- 627 ting down a TLS session, until Postfix times out. 628 629 Available in Postfix 3.5 and later: 630 631 <b><a href="postconf.5.html#info_log_address_format">info_log_address_format</a> (external)</b> 632 The email address form that will be used in non-debug logging 633 (info, warning, etc.). 634 635<b>OBSOLETE STARTTLS CONTROLS</b> 636 The following configuration parameters exist for compatibility with 637 Postfix versions before 2.3. Support for these will be removed in a 638 future release. 639 640 <b><a href="postconf.5.html#smtpd_use_tls">smtpd_use_tls</a> (no)</b> 641 Opportunistic TLS: announce STARTTLS support to remote SMTP 642 clients, but do not require that clients use TLS encryption. 643 644 <b><a href="postconf.5.html#smtpd_enforce_tls">smtpd_enforce_tls</a> (no)</b> 645 Mandatory TLS: announce STARTTLS support to remote SMTP clients, 646 and require that clients use TLS encryption. 647 648 <b><a href="postconf.5.html#smtpd_tls_cipherlist">smtpd_tls_cipherlist</a> (empty)</b> 649 Obsolete Postfix < 2.3 control for the Postfix SMTP server TLS 650 cipher list. 651 652<b>SMTPUTF8 CONTROLS</b> 653 Preliminary SMTPUTF8 support is introduced with Postfix 3.0. 654 655 <b><a href="postconf.5.html#smtputf8_enable">smtputf8_enable</a> (yes)</b> 656 Enable preliminary SMTPUTF8 support for the protocols described 657 in <a href="https://tools.ietf.org/html/rfc6531">RFC 6531</a>..6533. 658 659 <b><a href="postconf.5.html#strict_smtputf8">strict_smtputf8</a> (no)</b> 660 Enable stricter enforcement of the SMTPUTF8 protocol. 661 662 <b><a href="postconf.5.html#smtputf8_autodetect_classes">smtputf8_autodetect_classes</a> (sendmail, verify)</b> 663 Detect that a message requires SMTPUTF8 support for the speci- 664 fied mail origin classes. 665 666 Available in Postfix version 3.2 and later: 667 668 <b><a href="postconf.5.html#enable_idna2003_compatibility">enable_idna2003_compatibility</a> (no)</b> 669 Enable 'transitional' compatibility between IDNA2003 and 670 IDNA2008, when converting UTF-8 domain names to/from the ASCII 671 form that is used for DNS lookups. 672 673<b>VERP SUPPORT CONTROLS</b> 674 With VERP style delivery, each recipient of a message receives a cus- 675 tomized copy of the message with his/her own recipient address encoded 676 in the envelope sender address. The <a href="VERP_README.html">VERP_README</a> file describes config- 677 uration and operation details of Postfix support for variable envelope 678 return path addresses. VERP style delivery is requested with the SMTP 679 XVERP command or with the "sendmail -V" command-line option and is 680 available in Postfix version 1.1 and later. 681 682 <b><a href="postconf.5.html#default_verp_delimiters">default_verp_delimiters</a> (+=)</b> 683 The two default VERP delimiter characters. 684 685 <b><a href="postconf.5.html#verp_delimiter_filter">verp_delimiter_filter</a> (-=+)</b> 686 The characters Postfix accepts as VERP delimiter characters on 687 the Postfix <a href="sendmail.1.html"><b>sendmail</b>(1)</a> command line and in SMTP commands. 688 689 Available in Postfix version 1.1 and 2.0: 690 691 <b><a href="postconf.5.html#authorized_verp_clients">authorized_verp_clients</a> ($<a href="postconf.5.html#mynetworks">mynetworks</a>)</b> 692 What remote SMTP clients are allowed to specify the XVERP com- 693 mand. 694 695 Available in Postfix version 2.1 and later: 696 697 <b><a href="postconf.5.html#smtpd_authorized_verp_clients">smtpd_authorized_verp_clients</a> ($<a href="postconf.5.html#authorized_verp_clients">authorized_verp_clients</a>)</b> 698 What remote SMTP clients are allowed to specify the XVERP com- 699 mand. 700 701<b>TROUBLE SHOOTING CONTROLS</b> 702 The <a href="DEBUG_README.html">DEBUG_README</a> document describes how to debug parts of the Postfix 703 mail system. The methods vary from making the software log a lot of 704 detail, to running some daemon processes under control of a call tracer 705 or debugger. 706 707 <b><a href="postconf.5.html#debug_peer_level">debug_peer_level</a> (2)</b> 708 The increment in verbose logging level when a nexthop destina- 709 tion, remote client or server name or network address matches a 710 pattern given with the <a href="postconf.5.html#debug_peer_list">debug_peer_list</a> parameter. 711 712 <b><a href="postconf.5.html#debug_peer_list">debug_peer_list</a> (empty)</b> 713 Optional list of nexthop destination, remote client or server 714 name or network address patterns that, if matched, cause the 715 verbose logging level to increase by the amount specified in 716 $<a href="postconf.5.html#debug_peer_level">debug_peer_level</a>. 717 718 <b><a href="postconf.5.html#error_notice_recipient">error_notice_recipient</a> (postmaster)</b> 719 The recipient of postmaster notifications about mail delivery 720 problems that are caused by policy, resource, software or proto- 721 col errors. 722 723 <b><a href="postconf.5.html#internal_mail_filter_classes">internal_mail_filter_classes</a> (empty)</b> 724 What categories of Postfix-generated mail are subject to 725 before-queue content inspection by <a href="postconf.5.html#non_smtpd_milters">non_smtpd_milters</a>, 726 <a href="postconf.5.html#header_checks">header_checks</a> and <a href="postconf.5.html#body_checks">body_checks</a>. 727 728 <b><a href="postconf.5.html#notify_classes">notify_classes</a> (resource, software)</b> 729 The list of error classes that are reported to the postmaster. 730 731 <b><a href="postconf.5.html#smtpd_reject_footer">smtpd_reject_footer</a> (empty)</b> 732 Optional information that is appended after each Postfix SMTP 733 server 4XX or 5XX response. 734 735 <b><a href="postconf.5.html#soft_bounce">soft_bounce</a> (no)</b> 736 Safety net to keep mail queued that would otherwise be returned 737 to the sender. 738 739 Available in Postfix version 2.1 and later: 740 741 <b><a href="postconf.5.html#smtpd_authorized_xclient_hosts">smtpd_authorized_xclient_hosts</a> (empty)</b> 742 What remote SMTP clients are allowed to use the XCLIENT feature. 743 744 Available in Postfix version 2.10 and later: 745 746 <b><a href="postconf.5.html#smtpd_log_access_permit_actions">smtpd_log_access_permit_actions</a> (empty)</b> 747 Enable logging of the named "permit" actions in SMTP server 748 access lists (by default, the SMTP server logs "reject" actions 749 but not "permit" actions). 750 751<b>KNOWN VERSUS UNKNOWN RECIPIENT CONTROLS</b> 752 As of Postfix version 2.0, the SMTP server rejects mail for unknown 753 recipients. This prevents the mail queue from clogging up with undeliv- 754 erable MAILER-DAEMON messages. Additional information on this topic is 755 in the <a href="LOCAL_RECIPIENT_README.html">LOCAL_RECIPIENT_README</a> and <a href="ADDRESS_CLASS_README.html">ADDRESS_CLASS_README</a> documents. 756 757 <b><a href="postconf.5.html#show_user_unknown_table_name">show_user_unknown_table_name</a> (yes)</b> 758 Display the name of the recipient table in the "User unknown" 759 responses. 760 761 <b><a href="postconf.5.html#canonical_maps">canonical_maps</a> (empty)</b> 762 Optional address mapping lookup tables for message headers and 763 envelopes. 764 765 <b><a href="postconf.5.html#recipient_canonical_maps">recipient_canonical_maps</a> (empty)</b> 766 Optional address mapping lookup tables for envelope and header 767 recipient addresses. 768 769 <b><a href="postconf.5.html#sender_canonical_maps">sender_canonical_maps</a> (empty)</b> 770 Optional address mapping lookup tables for envelope and header 771 sender addresses. 772 773 Parameters concerning known/unknown local recipients: 774 775 <b><a href="postconf.5.html#mydestination">mydestination</a> ($<a href="postconf.5.html#myhostname">myhostname</a>, localhost.$<a href="postconf.5.html#mydomain">mydomain</a>, localhost)</b> 776 The list of domains that are delivered via the $<a href="postconf.5.html#local_transport">local_transport</a> 777 mail delivery transport. 778 779 <b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a> (all)</b> 780 The network interface addresses that this mail system receives 781 mail on. 782 783 <b><a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a> (empty)</b> 784 The network interface addresses that this mail system receives 785 mail on by way of a proxy or network address translation unit. 786 787 <b><a href="postconf.5.html#inet_protocols">inet_protocols</a> (see 'postconf -d output')</b> 788 The Internet protocols Postfix will attempt to use when making 789 or accepting connections. 790 791 <b><a href="postconf.5.html#local_recipient_maps">local_recipient_maps</a> (<a href="proxymap.8.html">proxy</a>:unix:passwd.byname $<a href="postconf.5.html#alias_maps">alias_maps</a>)</b> 792 Lookup tables with all names or addresses of local recipients: a 793 recipient address is local when its domain matches $<a href="postconf.5.html#mydestination">mydestina</a>- 794 <a href="postconf.5.html#mydestination">tion</a>, $<a href="postconf.5.html#inet_interfaces">inet_interfaces</a> or $<a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a>. 795 796 <b><a href="postconf.5.html#unknown_local_recipient_reject_code">unknown_local_recipient_reject_code</a> (550)</b> 797 The numerical Postfix SMTP server response code when a recipient 798 address is local, and $<a href="postconf.5.html#local_recipient_maps">local_recipient_maps</a> specifies a list of 799 lookup tables that does not match the recipient. 800 801 Parameters concerning known/unknown recipients of relay destinations: 802 803 <b><a href="postconf.5.html#relay_domains">relay_domains</a> (Postfix</b> ><b>= 3.0: empty, Postfix</b> < <b>3.0: $<a href="postconf.5.html#mydestination">mydestination</a>)</b> 804 What destination domains (and subdomains thereof) this system 805 will relay mail to. 806 807 <b><a href="postconf.5.html#relay_recipient_maps">relay_recipient_maps</a> (empty)</b> 808 Optional lookup tables with all valid addresses in the domains 809 that match $<a href="postconf.5.html#relay_domains">relay_domains</a>. 810 811 <b><a href="postconf.5.html#unknown_relay_recipient_reject_code">unknown_relay_recipient_reject_code</a> (550)</b> 812 The numerical Postfix SMTP server reply code when a recipient 813 address matches $<a href="postconf.5.html#relay_domains">relay_domains</a>, and <a href="postconf.5.html#relay_recipient_maps">relay_recipient_maps</a> speci- 814 fies a list of lookup tables that does not match the recipient 815 address. 816 817 Parameters concerning known/unknown recipients in virtual alias 818 domains: 819 820 <b><a href="postconf.5.html#virtual_alias_domains">virtual_alias_domains</a> ($<a href="postconf.5.html#virtual_alias_maps">virtual_alias_maps</a>)</b> 821 Postfix is final destination for the specified list of virtual 822 alias domains, that is, domains for which all addresses are 823 aliased to addresses in other local or remote domains. 824 825 <b><a href="postconf.5.html#virtual_alias_maps">virtual_alias_maps</a> ($<a href="postconf.5.html#virtual_maps">virtual_maps</a>)</b> 826 Optional lookup tables that alias specific mail addresses or 827 domains to other local or remote address. 828 829 <b><a href="postconf.5.html#unknown_virtual_alias_reject_code">unknown_virtual_alias_reject_code</a> (550)</b> 830 The Postfix SMTP server reply code when a recipient address 831 matches $<a href="postconf.5.html#virtual_alias_domains">virtual_alias_domains</a>, and $<a href="postconf.5.html#virtual_alias_maps">virtual_alias_maps</a> speci- 832 fies a list of lookup tables that does not match the recipient 833 address. 834 835 Parameters concerning known/unknown recipients in virtual mailbox 836 domains: 837 838 <b><a href="postconf.5.html#virtual_mailbox_domains">virtual_mailbox_domains</a> ($<a href="postconf.5.html#virtual_mailbox_maps">virtual_mailbox_maps</a>)</b> 839 Postfix is final destination for the specified list of domains; 840 mail is delivered via the $<a href="postconf.5.html#virtual_transport">virtual_transport</a> mail delivery 841 transport. 842 843 <b><a href="postconf.5.html#virtual_mailbox_maps">virtual_mailbox_maps</a> (empty)</b> 844 Optional lookup tables with all valid addresses in the domains 845 that match $<a href="postconf.5.html#virtual_mailbox_domains">virtual_mailbox_domains</a>. 846 847 <b><a href="postconf.5.html#unknown_virtual_mailbox_reject_code">unknown_virtual_mailbox_reject_code</a> (550)</b> 848 The Postfix SMTP server reply code when a recipient address 849 matches $<a href="postconf.5.html#virtual_mailbox_domains">virtual_mailbox_domains</a>, and $<a href="postconf.5.html#virtual_mailbox_maps">virtual_mailbox_maps</a> 850 specifies a list of lookup tables that does not match the recip- 851 ient address. 852 853<b>RESOURCE AND RATE CONTROLS</b> 854 The following parameters limit resource usage by the SMTP server and/or 855 control client request rates. 856 857 <b><a href="postconf.5.html#line_length_limit">line_length_limit</a> (2048)</b> 858 Upon input, long lines are chopped up into pieces of at most 859 this length; upon delivery, long lines are reconstructed. 860 861 <b><a href="postconf.5.html#queue_minfree">queue_minfree</a> (0)</b> 862 The minimal amount of free space in bytes in the queue file sys- 863 tem that is needed to receive mail. 864 865 <b><a href="postconf.5.html#message_size_limit">message_size_limit</a> (10240000)</b> 866 The maximal size in bytes of a message, including envelope 867 information. 868 869 <b><a href="postconf.5.html#smtpd_recipient_limit">smtpd_recipient_limit</a> (1000)</b> 870 The maximal number of recipients that the Postfix SMTP server 871 accepts per message delivery request. 872 873 <b><a href="postconf.5.html#smtpd_timeout">smtpd_timeout</a> (normal: 300s, overload: 10s)</b> 874 When the Postfix SMTP server wants to send an SMTP server 875 response, how long the Postfix SMTP server will wait for an 876 underlying network write operation to complete; and when the 877 Postfix SMTP server Postfix wants to receive an SMTP client 878 request, how long the Postfix SMTP server will wait for an 879 underlying network read operation to complete. 880 881 <b><a href="postconf.5.html#smtpd_history_flush_threshold">smtpd_history_flush_threshold</a> (100)</b> 882 The maximal number of lines in the Postfix SMTP server command 883 history before it is flushed upon receipt of EHLO, RSET, or end 884 of DATA. 885 886 Available in Postfix version 2.3 and later: 887 888 <b><a href="postconf.5.html#smtpd_peername_lookup">smtpd_peername_lookup</a> (yes)</b> 889 Attempt to look up the remote SMTP client hostname, and verify 890 that the name matches the client IP address. 891 892 The per SMTP client connection count and request rate limits are imple- 893 mented in co-operation with the <a href="anvil.8.html"><b>anvil</b>(8)</a> service, and are available in 894 Postfix version 2.2 and later. 895 896 <b><a href="postconf.5.html#smtpd_client_connection_count_limit">smtpd_client_connection_count_limit</a> (50)</b> 897 How many simultaneous connections any client is allowed to make 898 to this service. 899 900 <b><a href="postconf.5.html#smtpd_client_connection_rate_limit">smtpd_client_connection_rate_limit</a> (0)</b> 901 The maximal number of connection attempts any client is allowed 902 to make to this service per time unit. 903 904 <b><a href="postconf.5.html#smtpd_client_message_rate_limit">smtpd_client_message_rate_limit</a> (0)</b> 905 The maximal number of message delivery requests that any client 906 is allowed to make to this service per time unit, regardless of 907 whether or not Postfix actually accepts those messages. 908 909 <b><a href="postconf.5.html#smtpd_client_recipient_rate_limit">smtpd_client_recipient_rate_limit</a> (0)</b> 910 The maximal number of recipient addresses that any client is 911 allowed to send to this service per time unit, regardless of 912 whether or not Postfix actually accepts those recipients. 913 914 <b><a href="postconf.5.html#smtpd_client_event_limit_exceptions">smtpd_client_event_limit_exceptions</a> ($<a href="postconf.5.html#mynetworks">mynetworks</a>)</b> 915 Clients that are excluded from smtpd_client_*_count/rate_limit 916 restrictions. 917 918 Available in Postfix version 2.3 and later: 919 920 <b><a href="postconf.5.html#smtpd_client_new_tls_session_rate_limit">smtpd_client_new_tls_session_rate_limit</a> (0)</b> 921 The maximal number of new (i.e., uncached) TLS sessions that a 922 remote SMTP client is allowed to negotiate with this service per 923 time unit. 924 925 Available in Postfix version 2.9 - 3.6: 926 927 <b><a href="postconf.5.html#smtpd_per_record_deadline">smtpd_per_record_deadline</a> (normal: no, overload: yes)</b> 928 Change the behavior of the <a href="postconf.5.html#smtpd_timeout">smtpd_timeout</a> and <a href="postconf.5.html#smtpd_starttls_timeout">smtpd_start</a>- 929 <a href="postconf.5.html#smtpd_starttls_timeout">tls_timeout</a> time limits, from a time limit per read or write 930 system call, to a time limit to send or receive a complete 931 record (an SMTP command line, SMTP response line, SMTP message 932 content line, or TLS protocol message). 933 934 Available in Postfix version 3.1 and later: 935 936 <b><a href="postconf.5.html#smtpd_client_auth_rate_limit">smtpd_client_auth_rate_limit</a> (0)</b> 937 The maximal number of AUTH commands that any client is allowed 938 to send to this service per time unit, regardless of whether or 939 not Postfix actually accepts those commands. 940 941 Available in Postfix version 3.7 and later: 942 943 <b><a href="postconf.5.html#smtpd_per_request_deadline">smtpd_per_request_deadline</a> (normal: no, overload: yes)</b> 944 Change the behavior of the <a href="postconf.5.html#smtpd_timeout">smtpd_timeout</a> and <a href="postconf.5.html#smtpd_starttls_timeout">smtpd_start</a>- 945 <a href="postconf.5.html#smtpd_starttls_timeout">tls_timeout</a> time limits, from a time limit per plaintext or TLS 946 read or write call, to a combined time limit for receiving a 947 complete SMTP request and for sending a complete SMTP response. 948 949 <b><a href="postconf.5.html#smtpd_min_data_rate">smtpd_min_data_rate</a> (500)</b> 950 The minimum plaintext data transfer rate in bytes/second for 951 DATA and BDAT requests, when deadlines are enabled with 952 <a href="postconf.5.html#smtpd_per_request_deadline">smtpd_per_request_deadline</a>. 953 954 <b><a href="postconf.5.html#header_from_format">header_from_format</a> (standard)</b> 955 The format of the Postfix-generated <b>From:</b> header. 956 957<b>TARPIT CONTROLS</b> 958 When a remote SMTP client makes errors, the Postfix SMTP server can 959 insert delays before responding. This can help to slow down run-away 960 software. The behavior is controlled by an error counter that counts 961 the number of errors within an SMTP session that a client makes without 962 delivering mail. 963 964 <b><a href="postconf.5.html#smtpd_error_sleep_time">smtpd_error_sleep_time</a> (1s)</b> 965 With Postfix version 2.1 and later: the SMTP server response 966 delay after a client has made more than $<a href="postconf.5.html#smtpd_soft_error_limit">smtpd_soft_error_limit</a> 967 errors, and fewer than $<a href="postconf.5.html#smtpd_hard_error_limit">smtpd_hard_error_limit</a> errors, without 968 delivering mail. 969 970 <b><a href="postconf.5.html#smtpd_soft_error_limit">smtpd_soft_error_limit</a> (10)</b> 971 The number of errors a remote SMTP client is allowed to make 972 without delivering mail before the Postfix SMTP server slows 973 down all its responses. 974 975 <b><a href="postconf.5.html#smtpd_hard_error_limit">smtpd_hard_error_limit</a> (normal: 20, overload: 1)</b> 976 The maximal number of errors a remote SMTP client is allowed to 977 make without delivering mail. 978 979 <b><a href="postconf.5.html#smtpd_junk_command_limit">smtpd_junk_command_limit</a> (normal: 100, overload: 1)</b> 980 The number of junk commands (NOOP, VRFY, ETRN or RSET) that a 981 remote SMTP client can send before the Postfix SMTP server 982 starts to increment the error counter with each junk command. 983 984 Available in Postfix version 2.1 and later: 985 986 <b><a href="postconf.5.html#smtpd_recipient_overshoot_limit">smtpd_recipient_overshoot_limit</a> (1000)</b> 987 The number of recipients that a remote SMTP client can send in 988 excess of the limit specified with $<a href="postconf.5.html#smtpd_recipient_limit">smtpd_recipient_limit</a>, 989 before the Postfix SMTP server increments the per-session error 990 count for each excess recipient. 991 992<b>ACCESS POLICY DELEGATION CONTROLS</b> 993 As of version 2.1, Postfix can be configured to delegate access policy 994 decisions to an external server that runs outside Postfix. See the 995 file <a href="SMTPD_POLICY_README.html">SMTPD_POLICY_README</a> for more information. 996 997 <b><a href="postconf.5.html#smtpd_policy_service_max_idle">smtpd_policy_service_max_idle</a> (300s)</b> 998 The time after which an idle SMTPD policy service connection is 999 closed. 1000 1001 <b><a href="postconf.5.html#smtpd_policy_service_max_ttl">smtpd_policy_service_max_ttl</a> (1000s)</b> 1002 The time after which an active SMTPD policy service connection 1003 is closed. 1004 1005 <b><a href="postconf.5.html#smtpd_policy_service_timeout">smtpd_policy_service_timeout</a> (100s)</b> 1006 The time limit for connecting to, writing to, or receiving from 1007 a delegated SMTPD policy server. 1008 1009 Available in Postfix version 3.0 and later: 1010 1011 <b><a href="postconf.5.html#smtpd_policy_service_default_action">smtpd_policy_service_default_action</a> (451 4.3.5 Server configuration</b> 1012 <b>problem)</b> 1013 The default action when an SMTPD policy service request fails. 1014 1015 <b><a href="postconf.5.html#smtpd_policy_service_request_limit">smtpd_policy_service_request_limit</a> (0)</b> 1016 The maximal number of requests per SMTPD policy service connec- 1017 tion, or zero (no limit). 1018 1019 <b><a href="postconf.5.html#smtpd_policy_service_try_limit">smtpd_policy_service_try_limit</a> (2)</b> 1020 The maximal number of attempts to send an SMTPD policy service 1021 request before giving up. 1022 1023 <b><a href="postconf.5.html#smtpd_policy_service_retry_delay">smtpd_policy_service_retry_delay</a> (1s)</b> 1024 The delay between attempts to resend a failed SMTPD policy ser- 1025 vice request. 1026 1027 Available in Postfix version 3.1 and later: 1028 1029 <b><a href="postconf.5.html#smtpd_policy_service_policy_context">smtpd_policy_service_policy_context</a> (empty)</b> 1030 Optional information that the Postfix SMTP server specifies in 1031 the "policy_context" attribute of a policy service request 1032 (originally, to share the same service endpoint among multiple 1033 <a href="postconf.5.html#check_policy_service">check_policy_service</a> clients). 1034 1035<b>ACCESS CONTROLS</b> 1036 The <a href="SMTPD_ACCESS_README.html">SMTPD_ACCESS_README</a> document gives an introduction to all the SMTP 1037 server access control features. 1038 1039 <b><a href="postconf.5.html#smtpd_delay_reject">smtpd_delay_reject</a> (yes)</b> 1040 Wait until the RCPT TO command before evaluating 1041 $<a href="postconf.5.html#smtpd_client_restrictions">smtpd_client_restrictions</a>, $<a href="postconf.5.html#smtpd_helo_restrictions">smtpd_helo_restrictions</a> and 1042 $<a href="postconf.5.html#smtpd_sender_restrictions">smtpd_sender_restrictions</a>, or wait until the ETRN command 1043 before evaluating $<a href="postconf.5.html#smtpd_client_restrictions">smtpd_client_restrictions</a> and 1044 $<a href="postconf.5.html#smtpd_helo_restrictions">smtpd_helo_restrictions</a>. 1045 1046 <b><a href="postconf.5.html#parent_domain_matches_subdomains">parent_domain_matches_subdomains</a> (see 'postconf -d' output)</b> 1047 A list of Postfix features where the pattern "example.com" also 1048 matches subdomains of example.com, instead of requiring an 1049 explicit ".example.com" pattern. 1050 1051 <b><a href="postconf.5.html#smtpd_client_restrictions">smtpd_client_restrictions</a> (empty)</b> 1052 Optional restrictions that the Postfix SMTP server applies in 1053 the context of a client connection request. 1054 1055 <b><a href="postconf.5.html#smtpd_helo_required">smtpd_helo_required</a> (no)</b> 1056 Require that a remote SMTP client introduces itself with the 1057 HELO or EHLO command before sending the MAIL command or other 1058 commands that require EHLO negotiation. 1059 1060 <b><a href="postconf.5.html#smtpd_helo_restrictions">smtpd_helo_restrictions</a> (empty)</b> 1061 Optional restrictions that the Postfix SMTP server applies in 1062 the context of a client HELO command. 1063 1064 <b><a href="postconf.5.html#smtpd_sender_restrictions">smtpd_sender_restrictions</a> (empty)</b> 1065 Optional restrictions that the Postfix SMTP server applies in 1066 the context of a client MAIL FROM command. 1067 1068 <b><a href="postconf.5.html#smtpd_recipient_restrictions">smtpd_recipient_restrictions</a> (see 'postconf -d' output)</b> 1069 Optional restrictions that the Postfix SMTP server applies in 1070 the context of a client RCPT TO command, after 1071 <a href="postconf.5.html#smtpd_relay_restrictions">smtpd_relay_restrictions</a>. 1072 1073 <b><a href="postconf.5.html#smtpd_etrn_restrictions">smtpd_etrn_restrictions</a> (empty)</b> 1074 Optional restrictions that the Postfix SMTP server applies in 1075 the context of a client ETRN command. 1076 1077 <b><a href="postconf.5.html#allow_untrusted_routing">allow_untrusted_routing</a> (no)</b> 1078 Forward mail with sender-specified routing 1079 (user[@%!]remote[@%!]site) from untrusted clients to destina- 1080 tions matching $<a href="postconf.5.html#relay_domains">relay_domains</a>. 1081 1082 <b><a href="postconf.5.html#smtpd_restriction_classes">smtpd_restriction_classes</a> (empty)</b> 1083 User-defined aliases for groups of access restrictions. 1084 1085 <b><a href="postconf.5.html#smtpd_null_access_lookup_key">smtpd_null_access_lookup_key</a> (</b><><b>)</b> 1086 The lookup key to be used in SMTP <a href="access.5.html"><b>access</b>(5)</a> tables instead of 1087 the null sender address. 1088 1089 <b><a href="postconf.5.html#permit_mx_backup_networks">permit_mx_backup_networks</a> (empty)</b> 1090 Restrict the use of the <a href="postconf.5.html#permit_mx_backup">permit_mx_backup</a> SMTP access feature to 1091 only domains whose primary MX hosts match the listed networks. 1092 1093 Available in Postfix version 2.0 and later: 1094 1095 <b><a href="postconf.5.html#smtpd_data_restrictions">smtpd_data_restrictions</a> (empty)</b> 1096 Optional access restrictions that the Postfix SMTP server 1097 applies in the context of the SMTP DATA command. 1098 1099 <b><a href="postconf.5.html#smtpd_expansion_filter">smtpd_expansion_filter</a> (see 'postconf -d' output)</b> 1100 What characters are allowed in $name expansions of RBL reply 1101 templates. 1102 1103 Available in Postfix version 2.1 and later: 1104 1105 <b><a href="postconf.5.html#smtpd_reject_unlisted_sender">smtpd_reject_unlisted_sender</a> (no)</b> 1106 Request that the Postfix SMTP server rejects mail from unknown 1107 sender addresses, even when no explicit <a href="postconf.5.html#reject_unlisted_sender">reject_unlisted_sender</a> 1108 access restriction is specified. 1109 1110 <b><a href="postconf.5.html#smtpd_reject_unlisted_recipient">smtpd_reject_unlisted_recipient</a> (yes)</b> 1111 Request that the Postfix SMTP server rejects mail for unknown 1112 recipient addresses, even when no explicit 1113 <a href="postconf.5.html#reject_unlisted_recipient">reject_unlisted_recipient</a> access restriction is specified. 1114 1115 Available in Postfix version 2.2 and later: 1116 1117 <b><a href="postconf.5.html#smtpd_end_of_data_restrictions">smtpd_end_of_data_restrictions</a> (empty)</b> 1118 Optional access restrictions that the Postfix SMTP server 1119 applies in the context of the SMTP END-OF-DATA command. 1120 1121 Available in Postfix version 2.10 and later: 1122 1123 <b><a href="postconf.5.html#smtpd_relay_restrictions">smtpd_relay_restrictions</a> (<a href="postconf.5.html#permit_mynetworks">permit_mynetworks</a>, <a href="postconf.5.html#permit_sasl_authenticated">permit_sasl_authenticated</a>,</b> 1124 <b><a href="postconf.5.html#defer_unauth_destination">defer_unauth_destination</a>)</b> 1125 Access restrictions for mail relay control that the Postfix SMTP 1126 server applies in the context of the RCPT TO command, before 1127 <a href="postconf.5.html#smtpd_recipient_restrictions">smtpd_recipient_restrictions</a>. 1128 1129<b>SENDER AND RECIPIENT ADDRESS VERIFICATION CONTROLS</b> 1130 Postfix version 2.1 introduces sender and recipient address verifica- 1131 tion. This feature is implemented by sending probe email messages that 1132 are not actually delivered. This feature is requested via the 1133 <a href="postconf.5.html#reject_unverified_sender">reject_unverified_sender</a> and <a href="postconf.5.html#reject_unverified_recipient">reject_unverified_recipient</a> access 1134 restrictions. The status of verification probes is maintained by the 1135 <a href="verify.8.html"><b>verify</b>(8)</a> server. See the file <a href="ADDRESS_VERIFICATION_README.html">ADDRESS_VERIFICATION_README</a> for infor- 1136 mation about how to configure and operate the Postfix sender/recipient 1137 address verification service. 1138 1139 <b><a href="postconf.5.html#address_verify_poll_count">address_verify_poll_count</a> (normal: 3, overload: 1)</b> 1140 How many times to query the <a href="verify.8.html"><b>verify</b>(8)</a> service for the completion 1141 of an address verification request in progress. 1142 1143 <b><a href="postconf.5.html#address_verify_poll_delay">address_verify_poll_delay</a> (3s)</b> 1144 The delay between queries for the completion of an address veri- 1145 fication request in progress. 1146 1147 <b><a href="postconf.5.html#address_verify_sender">address_verify_sender</a> ($<a href="postconf.5.html#double_bounce_sender">double_bounce_sender</a>)</b> 1148 The sender address to use in address verification probes; prior 1149 to Postfix 2.5 the default was "postmaster". 1150 1151 <b><a href="postconf.5.html#unverified_sender_reject_code">unverified_sender_reject_code</a> (450)</b> 1152 The numerical Postfix SMTP server response code when a recipient 1153 address is rejected by the <a href="postconf.5.html#reject_unverified_sender">reject_unverified_sender</a> restriction. 1154 1155 <b><a href="postconf.5.html#unverified_recipient_reject_code">unverified_recipient_reject_code</a> (450)</b> 1156 The numerical Postfix SMTP server response when a recipient 1157 address is rejected by the <a href="postconf.5.html#reject_unverified_recipient">reject_unverified_recipient</a> restric- 1158 tion. 1159 1160 Available in Postfix version 2.6 and later: 1161 1162 <b><a href="postconf.5.html#unverified_sender_defer_code">unverified_sender_defer_code</a> (450)</b> 1163 The numerical Postfix SMTP server response code when a sender 1164 address probe fails due to a temporary error condition. 1165 1166 <b><a href="postconf.5.html#unverified_recipient_defer_code">unverified_recipient_defer_code</a> (450)</b> 1167 The numerical Postfix SMTP server response when a recipient 1168 address probe fails due to a temporary error condition. 1169 1170 <b><a href="postconf.5.html#unverified_sender_reject_reason">unverified_sender_reject_reason</a> (empty)</b> 1171 The Postfix SMTP server's reply when rejecting mail with 1172 <a href="postconf.5.html#reject_unverified_sender">reject_unverified_sender</a>. 1173 1174 <b><a href="postconf.5.html#unverified_recipient_reject_reason">unverified_recipient_reject_reason</a> (empty)</b> 1175 The Postfix SMTP server's reply when rejecting mail with 1176 <a href="postconf.5.html#reject_unverified_recipient">reject_unverified_recipient</a>. 1177 1178 <b><a href="postconf.5.html#unverified_sender_tempfail_action">unverified_sender_tempfail_action</a> ($<a href="postconf.5.html#reject_tempfail_action">reject_tempfail_action</a>)</b> 1179 The Postfix SMTP server's action when <a href="postconf.5.html#reject_unverified_sender">reject_unverified_sender</a> 1180 fails due to a temporary error condition. 1181 1182 <b><a href="postconf.5.html#unverified_recipient_tempfail_action">unverified_recipient_tempfail_action</a> ($<a href="postconf.5.html#reject_tempfail_action">reject_tempfail_action</a>)</b> 1183 The Postfix SMTP server's action when <a href="postconf.5.html#reject_unverified_recipient">reject_unverified_recipi</a>- 1184 <a href="postconf.5.html#reject_unverified_recipient">ent</a> fails due to a temporary error condition. 1185 1186 Available with Postfix 2.9 and later: 1187 1188 <b><a href="postconf.5.html#address_verify_sender_ttl">address_verify_sender_ttl</a> (0s)</b> 1189 The time between changes in the time-dependent portion of 1190 address verification probe sender addresses. 1191 1192<b>ACCESS CONTROL RESPONSES</b> 1193 The following parameters control numerical SMTP reply codes and/or text 1194 responses. 1195 1196 <b><a href="postconf.5.html#access_map_reject_code">access_map_reject_code</a> (554)</b> 1197 The numerical Postfix SMTP server response code for an <a href="access.5.html"><b>access</b>(5)</a> 1198 map "reject" action. 1199 1200 <b><a href="postconf.5.html#defer_code">defer_code</a> (450)</b> 1201 The numerical Postfix SMTP server response code when a remote 1202 SMTP client request is rejected by the "defer" restriction. 1203 1204 <b><a href="postconf.5.html#invalid_hostname_reject_code">invalid_hostname_reject_code</a> (501)</b> 1205 The numerical Postfix SMTP server response code when the client 1206 HELO or EHLO command parameter is rejected by the 1207 <a href="postconf.5.html#reject_invalid_helo_hostname">reject_invalid_helo_hostname</a> restriction. 1208 1209 <b><a href="postconf.5.html#maps_rbl_reject_code">maps_rbl_reject_code</a> (554)</b> 1210 The numerical Postfix SMTP server response code when a remote 1211 SMTP client request is blocked by the <a href="postconf.5.html#reject_rbl_client">reject_rbl_client</a>, 1212 <a href="postconf.5.html#reject_rhsbl_client">reject_rhsbl_client</a>, <a href="postconf.5.html#reject_rhsbl_reverse_client">reject_rhsbl_reverse_client</a>, 1213 <a href="postconf.5.html#reject_rhsbl_sender">reject_rhsbl_sender</a> or <a href="postconf.5.html#reject_rhsbl_recipient">reject_rhsbl_recipient</a> restriction. 1214 1215 <b><a href="postconf.5.html#non_fqdn_reject_code">non_fqdn_reject_code</a> (504)</b> 1216 The numerical Postfix SMTP server reply code when a client 1217 request is rejected by the <a href="postconf.5.html#reject_non_fqdn_helo_hostname">reject_non_fqdn_helo_hostname</a>, 1218 <a href="postconf.5.html#reject_non_fqdn_sender">reject_non_fqdn_sender</a> or <a href="postconf.5.html#reject_non_fqdn_recipient">reject_non_fqdn_recipient</a> restriction. 1219 1220 <b><a href="postconf.5.html#plaintext_reject_code">plaintext_reject_code</a> (450)</b> 1221 The numerical Postfix SMTP server response code when a request 1222 is rejected by the <b><a href="postconf.5.html#reject_plaintext_session">reject_plaintext_session</a></b> restriction. 1223 1224 <b><a href="postconf.5.html#reject_code">reject_code</a> (554)</b> 1225 The numerical Postfix SMTP server response code when a remote 1226 SMTP client request is rejected by the "reject" restriction. 1227 1228 <b><a href="postconf.5.html#relay_domains_reject_code">relay_domains_reject_code</a> (554)</b> 1229 The numerical Postfix SMTP server response code when a client 1230 request is rejected by the <a href="postconf.5.html#reject_unauth_destination">reject_unauth_destination</a> recipient 1231 restriction. 1232 1233 <b><a href="postconf.5.html#unknown_address_reject_code">unknown_address_reject_code</a> (450)</b> 1234 The numerical response code when the Postfix SMTP server rejects 1235 a sender or recipient address because its domain is unknown. 1236 1237 <b><a href="postconf.5.html#unknown_client_reject_code">unknown_client_reject_code</a> (450)</b> 1238 The numerical Postfix SMTP server response code when a client 1239 without valid address <=> name mapping is rejected by the 1240 <a href="postconf.5.html#reject_unknown_client_hostname">reject_unknown_client_hostname</a> restriction. 1241 1242 <b><a href="postconf.5.html#unknown_hostname_reject_code">unknown_hostname_reject_code</a> (450)</b> 1243 The numerical Postfix SMTP server response code when the host- 1244 name specified with the HELO or EHLO command is rejected by the 1245 <a href="postconf.5.html#reject_unknown_helo_hostname">reject_unknown_helo_hostname</a> restriction. 1246 1247 Available in Postfix version 2.0 and later: 1248 1249 <b><a href="postconf.5.html#default_rbl_reply">default_rbl_reply</a> (see 'postconf -d' output)</b> 1250 The default Postfix SMTP server response template for a request 1251 that is rejected by an RBL-based restriction. 1252 1253 <b><a href="postconf.5.html#multi_recipient_bounce_reject_code">multi_recipient_bounce_reject_code</a> (550)</b> 1254 The numerical Postfix SMTP server response code when a remote 1255 SMTP client request is blocked by the <a href="postconf.5.html#reject_multi_recipient_bounce">reject_multi_recipi</a>- 1256 <a href="postconf.5.html#reject_multi_recipient_bounce">ent_bounce</a> restriction. 1257 1258 <b><a href="postconf.5.html#rbl_reply_maps">rbl_reply_maps</a> (empty)</b> 1259 Optional lookup tables with RBL response templates. 1260 1261 Available in Postfix version 2.6 and later: 1262 1263 <b><a href="postconf.5.html#access_map_defer_code">access_map_defer_code</a> (450)</b> 1264 The numerical Postfix SMTP server response code for an <a href="access.5.html"><b>access</b>(5)</a> 1265 map "defer" action, including "<a href="postconf.5.html#defer_if_permit">defer_if_permit</a>" or 1266 "<a href="postconf.5.html#defer_if_reject">defer_if_reject</a>". 1267 1268 <b><a href="postconf.5.html#reject_tempfail_action">reject_tempfail_action</a> (<a href="postconf.5.html#defer_if_permit">defer_if_permit</a>)</b> 1269 The Postfix SMTP server's action when a reject-type restriction 1270 fails due to a temporary error condition. 1271 1272 <b><a href="postconf.5.html#unknown_helo_hostname_tempfail_action">unknown_helo_hostname_tempfail_action</a> ($<a href="postconf.5.html#reject_tempfail_action">reject_tempfail_action</a>)</b> 1273 The Postfix SMTP server's action when <a href="postconf.5.html#reject_unknown_helo_hostname">reject_unknown_helo_host</a>- 1274 <a href="postconf.5.html#reject_unknown_helo_hostname">name</a> fails due to a temporary error condition. 1275 1276 <b><a href="postconf.5.html#unknown_address_tempfail_action">unknown_address_tempfail_action</a> ($<a href="postconf.5.html#reject_tempfail_action">reject_tempfail_action</a>)</b> 1277 The Postfix SMTP server's action when 1278 <a href="postconf.5.html#reject_unknown_sender_domain">reject_unknown_sender_domain</a> or <a href="postconf.5.html#reject_unknown_recipient_domain">reject_unknown_recipient_domain</a> 1279 fail due to a temporary error condition. 1280 1281<b>MISCELLANEOUS CONTROLS</b> 1282 <b><a href="postconf.5.html#config_directory">config_directory</a> (see 'postconf -d' output)</b> 1283 The default location of the Postfix <a href="postconf.5.html">main.cf</a> and <a href="master.5.html">master.cf</a> con- 1284 figuration files. 1285 1286 <b><a href="postconf.5.html#daemon_timeout">daemon_timeout</a> (18000s)</b> 1287 How much time a Postfix daemon process may take to handle a 1288 request before it is terminated by a built-in watchdog timer. 1289 1290 <b><a href="postconf.5.html#command_directory">command_directory</a> (see 'postconf -d' output)</b> 1291 The location of all postfix administrative commands. 1292 1293 <b><a href="postconf.5.html#double_bounce_sender">double_bounce_sender</a> (double-bounce)</b> 1294 The sender address of postmaster notifications that are gener- 1295 ated by the mail system. 1296 1297 <b><a href="postconf.5.html#ipc_timeout">ipc_timeout</a> (3600s)</b> 1298 The time limit for sending or receiving information over an 1299 internal communication channel. 1300 1301 <b><a href="postconf.5.html#mail_name">mail_name</a> (Postfix)</b> 1302 The mail system name that is displayed in Received: headers, in 1303 the SMTP greeting banner, and in bounced mail. 1304 1305 <b><a href="postconf.5.html#mail_owner">mail_owner</a> (postfix)</b> 1306 The UNIX system account that owns the Postfix queue and most 1307 Postfix daemon processes. 1308 1309 <b><a href="postconf.5.html#max_idle">max_idle</a> (100s)</b> 1310 The maximum amount of time that an idle Postfix daemon process 1311 waits for an incoming connection before terminating voluntarily. 1312 1313 <b><a href="postconf.5.html#max_use">max_use</a> (100)</b> 1314 The maximal number of incoming connections that a Postfix daemon 1315 process will service before terminating voluntarily. 1316 1317 <b><a href="postconf.5.html#myhostname">myhostname</a> (see 'postconf -d' output)</b> 1318 The internet hostname of this mail system. 1319 1320 <b><a href="postconf.5.html#mynetworks">mynetworks</a> (see 'postconf -d' output)</b> 1321 The list of "trusted" remote SMTP clients that have more privi- 1322 leges than "strangers". 1323 1324 <b><a href="postconf.5.html#myorigin">myorigin</a> ($<a href="postconf.5.html#myhostname">myhostname</a>)</b> 1325 The domain name that locally-posted mail appears to come from, 1326 and that locally posted mail is delivered to. 1327 1328 <b><a href="postconf.5.html#process_id">process_id</a> (read-only)</b> 1329 The process ID of a Postfix command or daemon process. 1330 1331 <b><a href="postconf.5.html#process_name">process_name</a> (read-only)</b> 1332 The process name of a Postfix command or daemon process. 1333 1334 <b><a href="postconf.5.html#queue_directory">queue_directory</a> (see 'postconf -d' output)</b> 1335 The location of the Postfix top-level queue directory. 1336 1337 <b><a href="postconf.5.html#recipient_delimiter">recipient_delimiter</a> (empty)</b> 1338 The set of characters that can separate an email address local- 1339 part, user name, or a .forward file name from its extension. 1340 1341 <b><a href="postconf.5.html#smtpd_banner">smtpd_banner</a> ($<a href="postconf.5.html#myhostname">myhostname</a> ESMTP $<a href="postconf.5.html#mail_name">mail_name</a>)</b> 1342 The text that follows the 220 status code in the SMTP greeting 1343 banner. 1344 1345 <b><a href="postconf.5.html#syslog_facility">syslog_facility</a> (mail)</b> 1346 The syslog facility of Postfix logging. 1347 1348 <b><a href="postconf.5.html#syslog_name">syslog_name</a> (see 'postconf -d' output)</b> 1349 A prefix that is prepended to the process name in syslog 1350 records, so that, for example, "smtpd" becomes "prefix/smtpd". 1351 1352 Available in Postfix version 2.2 and later: 1353 1354 <b><a href="postconf.5.html#smtpd_forbidden_commands">smtpd_forbidden_commands</a> (CONNECT GET POST <a href="regexp_table.5.html">regexp</a>:{{/^[^A-Z]/ Bogus}})</b> 1355 List of commands that cause the Postfix SMTP server to immedi- 1356 ately terminate the session with a 221 code. 1357 1358 Available in Postfix version 2.5 and later: 1359 1360 <b><a href="postconf.5.html#smtpd_client_port_logging">smtpd_client_port_logging</a> (no)</b> 1361 Enable logging of the remote SMTP client port in addition to the 1362 hostname and IP address. 1363 1364 Available in Postfix 3.3 and later: 1365 1366 <b><a href="postconf.5.html#service_name">service_name</a> (read-only)</b> 1367 The <a href="master.5.html">master.cf</a> service name of a Postfix daemon process. 1368 1369 Available in Postfix 3.4 and later: 1370 1371 <b><a href="postconf.5.html#smtpd_reject_footer_maps">smtpd_reject_footer_maps</a> (empty)</b> 1372 Lookup tables, indexed by the complete Postfix SMTP server 4xx 1373 or 5xx response, with reject footer templates. 1374 1375<b>SEE ALSO</b> 1376 <a href="anvil.8.html">anvil(8)</a>, connection/rate limiting 1377 <a href="cleanup.8.html">cleanup(8)</a>, message canonicalization 1378 <a href="tlsmgr.8.html">tlsmgr(8)</a>, TLS session and PRNG management 1379 <a href="trivial-rewrite.8.html">trivial-rewrite(8)</a>, address resolver 1380 <a href="verify.8.html">verify(8)</a>, address verification service 1381 <a href="postconf.5.html">postconf(5)</a>, configuration parameters 1382 <a href="master.5.html">master(5)</a>, generic daemon options 1383 <a href="master.8.html">master(8)</a>, process manager 1384 <a href="postlogd.8.html">postlogd(8)</a>, Postfix logging 1385 syslogd(8), system logging 1386 1387<b>README FILES</b> 1388 <a href="ADDRESS_CLASS_README.html">ADDRESS_CLASS_README</a>, blocking unknown hosted or relay recipients 1389 <a href="ADDRESS_REWRITING_README.html">ADDRESS_REWRITING_README</a>, Postfix address manipulation 1390 <a href="BDAT_README.html">BDAT_README</a>, Postfix CHUNKING support 1391 <a href="FILTER_README.html">FILTER_README</a>, external after-queue content filter 1392 <a href="LOCAL_RECIPIENT_README.html">LOCAL_RECIPIENT_README</a>, blocking unknown local recipients 1393 <a href="MILTER_README.html">MILTER_README</a>, before-queue mail filter applications 1394 <a href="SMTPD_ACCESS_README.html">SMTPD_ACCESS_README</a>, built-in access policies 1395 <a href="SMTPD_POLICY_README.html">SMTPD_POLICY_README</a>, external policy server 1396 <a href="SMTPD_PROXY_README.html">SMTPD_PROXY_README</a>, external before-queue content filter 1397 <a href="SASL_README.html">SASL_README</a>, Postfix SASL howto 1398 <a href="TLS_README.html">TLS_README</a>, Postfix STARTTLS howto 1399 <a href="VERP_README.html">VERP_README</a>, Postfix XVERP extension 1400 <a href="XCLIENT_README.html">XCLIENT_README</a>, Postfix XCLIENT extension 1401 <a href="XFORWARD_README.html">XFORWARD_README</a>, Postfix XFORWARD extension 1402 1403<b>LICENSE</b> 1404 The Secure Mailer license must be distributed with this software. 1405 1406<b>AUTHOR(S)</b> 1407 Wietse Venema 1408 IBM T.J. Watson Research 1409 P.O. Box 704 1410 Yorktown Heights, NY 10598, USA 1411 1412 Wietse Venema 1413 Google, Inc. 1414 111 8th Avenue 1415 New York, NY 10011, USA 1416 1417 SASL support originally by: 1418 Till Franke 1419 SuSE Rhein/Main AG 1420 65760 Eschborn, Germany 1421 1422 TLS support originally by: 1423 Lutz Jaenicke 1424 BTU Cottbus 1425 Allgemeine Elektrotechnik 1426 Universitaetsplatz 3-4 1427 D-03044 Cottbus, Germany 1428 1429 Revised TLS support by: 1430 Victor Duchovni 1431 Morgan Stanley 1432 1433 SMTPD(8) 1434</pre> </body> </html> 1435