1Postfix Installation From Source Code 2 3------------------------------------------------------------------------------- 4 51 - Purpose of this document 6 7If you are using a pre-compiled version of Postfix, you should start with 8BASIC_CONFIGURATION_README and the general documentation referenced by it. 9INSTALL is only a bootstrap document to get Postfix up and running from scratch 10with the minimal number of steps; it should not be considered part of the 11general documentation. 12 13This document describes how to build, install and configure a Postfix system so 14that it can do one of the following: 15 16 * Send mail only, without changing an existing Sendmail installation. 17 * Send and receive mail via a virtual host interface, still without any 18 change to an existing Sendmail installation. 19 * Run Postfix instead of Sendmail. 20 21Topics covered in this document: 22 23 1. Purpose of this document 24 2. Typographical conventions 25 3. Documentation 26 4. Building on a supported system 27 5. Porting Postfix to an unsupported system 28 6. Installing the software after successful compilation 29 7. Configuring Postfix to send mail only 30 8. Configuring Postfix to send and receive mail via virtual interface 31 9. Running Postfix instead of Sendmail 3210. Mandatory configuration file edits 3311. To chroot or not to chroot 3412. Care and feeding of the Postfix system 35 362 - Typographical conventions 37 38In the instructions below, a command written as 39 40 # command 41 42should be executed as the superuser. 43 44A command written as 45 46 $ command 47 48should be executed as an unprivileged user. 49 503 - Documentation 51 52Documentation is available as README files (start with the file README_FILES/ 53AAAREADME), as HTML web pages (point your browser to "html/index.html") and as 54UNIX-style manual pages. 55 56You should view the README files with a pager such as more(1) or less(1), 57because the files use backspace characters in order to produce bold font. To 58print a README file without backspace characters, use the col(1) command. For 59example: 60 61 $ col -bx <file | lpr 62 63In order to view the manual pages before installing Postfix, point your MANPATH 64environment variable to the "man" subdirectory; be sure to use an absolute 65path. 66 67 $ export MANPATH; MANPATH="`pwd`/man:$MANPATH" 68 $ setenv MANPATH "`pwd`/man:$MANPATH" 69 70Of particular interest is the postconf(5) manual page that lists all the 500+ 71configuration parameters. The HTML version of this text makes it easy to 72navigate around. 73 74All Postfix source files have their own built-in manual page. Tools to extract 75those embedded manual pages are available in the mantools directory. 76 774 - Building on a supported system 78 79Postfix development happens on FreeBSD and MacOS X, with regular tests on Linux 80(Fedora, Ubuntu) and Solaris. Support for other systems relies on feedback from 81their users, and may not always be up-to-date. 82 83OpenBSD is partially supported. The libc resolver does not implement the 84documented "internal resolver options which are [...] set by changing fields in 85the _res structure" (documented in the OpenBSD 5.6 resolver(3) manpage). This 86results in too many DNS queries, and false positives for queries that should 87fail. 88 89Overview of topics: 90 91 * 4.1 - Getting started 92 * 4.2 - What compiler to use 93 * 4.3 - Building with Postfix position-independent executables (Postfix >= 94 3.0) 95 * 4.4 - Building with Postfix dynamically-linked libraries and database 96 plugins (Postfix >= 3.0) 97 * 4.5 - Building with optional features 98 * 4.6 - Overriding built-in parameter default settings 99 * 4.7 - Overriding other compile-time features 100 * 4.8 - Support for thousands of processes 101 * 4.9 - Compiling Postfix, at last 102 1034.1 - Getting started 104 105On Solaris, the "make" command and other development utilities are in /usr/ccs/ 106bin, so you MUST have /usr/ccs/bin in your command search path. If these files 107do not exist, you need to install the development packages first. 108 109If you need to build Postfix for multiple architectures from a single source- 110code tree, use the "lndir" command to build a shadow tree with symbolic links 111to the source files. 112 113If at any time in the build process you get messages like: "make: don't know 114how to ..." you should be able to recover by running the following command from 115the Postfix top-level directory: 116 117 $ make -f Makefile.init makefiles 118 119If you copied the Postfix source code after building it on another machine, it 120is a good idea to cd into the top-level directory and first do this: 121 122 $ make tidy 123 124This will get rid of any system dependencies left over from compiling the 125software elsewhere. 126 1274.2 - What compiler to use 128 129To build with GCC, or with the native compiler if people told me that is better 130for your system, just cd into the top-level Postfix directory of the source 131tree and type: 132 133 $ make 134 135To build with a non-default compiler, you need to specify the name of the 136compiler. Here are a few examples: 137 138 $ make makefiles CC=/opt/SUNWspro/bin/cc (Solaris) 139 $ make 140 141 $ make makefiles CC="/opt/ansic/bin/cc -Ae" (HP-UX) 142 $ make 143 144 $ make makefiles CC="purify cc" 145 $ make 146 147and so on. In some cases, optimization will be turned off automatically. 148 1494.3 - Building with Postfix position-independent executables (Postfix >= 3.0) 150 151On some systems Postfix can be built with Position-Independent Executables. PIE 152is used by the ASLR exploit mitigation technique (ASLR = Address-Space Layout 153Randomization): 154 155 $ make makefiles pie=yes ...other arguments... 156 157(Specify "make makefiles pie=no" to explicitly disable Postfix position- 158independent executable support). 159 160Postfix PIE support appears to work on Fedora Core 20, Ubuntu 14.04, FreeBSD 9 161and 10, and NetBSD 6 (all with the default system compilers). 162 163Whether the "pie=yes" above has any effect depends on the compiler. Some 164compilers always produce PIE executables, and some may even complain that the 165Postfix build option is redundant. 166 1674.4 - Building with Postfix dynamically-linked libraries and database plugins 168(Postfix >= 3.0) 169 170Postfix dynamically-linked library and database plugin support exists for 171recent versions of Linux, FreeBSD and MacOS X. Dynamically-linked library 172builds may become the default at some point in the future. 173 174Overview of topics: 175 176 * 4.4.1 Turning on Postfix dynamically-linked library support 177 * 4.4.2 Turning on Postfix database-plugin support 178 * 4.4.3 Customizing Postfix dynamically-linked libraries and database plugins 179 * 4.4.4 Tips for distribution maintainers 180 181Note: directories with Postfix dynamically-linked libraries or database plugins 182should contain only postfix-related files. Postfix dynamically-linked libraries 183and database plugins should not be installed in a "public" system directory 184such as /usr/lib or /usr/local/lib. Linking Postfix dynamically-linked library 185or database-plugin files into non-Postfix programs is not supported. Postfix 186dynamically-linked libraries and database plugins implement a Postfix-internal 187API that changes without maintaining compatibility. 188 1894.4.1 Turning on Postfix dynamically-linked library support 190 191Postfix can be built with Postfix dynamically-linked libraries (files typically 192named libpostfix-*.so). Postfix dynamically-linked libraries add minor run-time 193overhead and result in significantly-smaller Postfix executable files. 194 195Specify "shared=yes" on the "make makefiles" command line to build Postfix with 196dynamically-linked library support. 197 198 $ make makefiles shared=yes ...other arguments... 199 $ make 200 201(Specify "make makefiles shared=no" to explicitly disable Postfix dynamically- 202linked library support). 203 204This installs dynamically-linked libraries in $shlib_directory, typically /usr/ 205lib/postfix or /usr/local/lib/postfix, with file names libpostfix-name.so, 206where the name is a source-code directory name such as "util" or "global". 207 208See section 4.4.3 "Customizing Postfix dynamically-linked libraries and 209database plugins" below for how to customize the Postfix dynamically-linked 210library location, including support to upgrade a running mail system safely. 211 2124.4.2 Turning on Postfix database-plugin support 213 214Additionally, Postfix can be built to support dynamic loading of Postfix 215database clients (database plugins) with the Debian-style dynamicmaps feature. 216Postfix 3.0 supports dynamic loading of cdb:, ldap:, lmdb:, mysql:, pcre:, 217pgsql:, sdbm:, and sqlite: database clients. Dynamic loading is useful when you 218distribute or install pre-compiled Postfix packages. 219 220Specify "dynamicmaps=yes" on the "make makefiles" command line to build Postfix 221with support to dynamically load Postfix database clients with the Debian-style 222dynamicmaps feature. 223 224 $ make makefiles dynamicmaps=yes ...other arguments... 225 $ make 226 227(Specify "make makefiles dynamicmaps=no" to explicitly disable Postfix 228database-plugin support). 229 230This implicitly enables dynamically-linked library support, installs the 231configuration file dynamicmaps.cf in $meta_directory (usually, /etc/postfix or 232/usr/local/etc/postfix), and installs database plugins in $shlib_directory (see 233above). Database plugins are named postfix-type.so where the type is a database 234type such as "cdb" or "ldap". 235 236 NOTE: The Postfix 3.0 build procedure expects that you specify database 237 library dependencies with variables named AUXLIBS_CDB, AUXLIBS_LDAP, etc. 238 With Postfix 3.0 and later, the old AUXLIBS variable still supports 239 building a statically-loaded database client, but only the new AUXLIBS_CDB 240 etc. variables support building a dynamically-loaded or statically-loaded 241 CDB etc. database client. See CDB_README, LDAP_README, etc. for details. 242 243 Failure to follow this advice will defeat the purpose of dynamic database 244 client loading. Every Postfix executable file will have database library 245 dependencies. And that was exactly what dynamic database client loading was 246 meant to avoid. 247 248See the next section for how to customize the location and version of Postfix 249database plugins and the location of the file dynamicmaps.cf. 250 2514.4.3 Customizing Postfix dynamically-linked libraries and database plugins 252 253Customizing build-time and run-time options for Postfix dynamically-linked 254libraries and database plugins 255 256The build-time environment variables SHLIB_CFLAGS, SHLIB_RPATH, and 257SHLIB_SUFFIX provide control over how Postfix libraries and plugins are 258compiled, linked, and named. 259 260 $ make makefiles SHLIB_CFLAGS=flags SHLIB_RPATH=rpath SHLIB_SUFFIX=suffix 261 ...other arguments... 262 $ make 263 264See section 4.7 "Overriding other compile-time features" below for details. 265 266Customizing the location of Postfix dynamically-linked libraries and database 267plugins 268 269As a reminder, the directories with Postfix dynamically-linked libraries or 270database plugins should contain only Postfix-related files. Linking these files 271into other programs is not supported. 272 273To override the default location of Postfix dynamically-linked libraries and 274database plugins specify, for example: 275 276 $ make makefiles shared=yes shlib_directory=/usr/local/lib/postfix ... 277 278If you intend to upgrade Postfix without stopping the mail system, then you 279should append the Postfix release version to the shlib_directory pathname, to 280eliminate the possibility that programs will link with dynamically-linked 281libraries or database plugins from the wrong Postfix version. For example: 282 283 $ make makefiles shared=yes \ 284 shlib_directory=/usr/local/lib/postfix/MAIL_VERSION ... 285 286The command "make makefiles name=value..." will replace the string MAIL_VERSION 287at the end of a configuration parameter value with the Postfix release version. 288Do not try to specify something like $mail_version on this command line. This 289produces inconsistent results with different versions of the make(1) command. 290 291You can change the shlib_directory setting after Postfix is built, with "make 292install" or "make upgrade". However, you may have to run ldconfig if you change 293shlib_directory after Postfix is built (the symptom is that Postfix programs 294fail because the run-time linker cannot find the files libpostfix-*.so). No 295ldconfig command is needed if you keep the files libpostfix-*.so in the 296compiled-in default $shlib_directory location. 297 298 # make upgrade shlib_directory=/usr/local/lib/postfix ... 299 # make install shlib_directory=/usr/local/lib/postfix ... 300 301To append the Postfix release version to the pathname if you intend to upgrade 302Postfix without stopping the mail system: 303 304 # make upgrade shlib_directory=/usr/local/lib/postfix/MAIL_VERSION ... 305 # make install shlib_directory=/usr/local/lib/postfix/MAIL_VERSION ... 306 307See also the comments above for appending MAIL_VERSION with the "make 308makefiles" command. 309 310Customizing the location of dynamicmaps.cf and other files 311 312The meta_directory parameter has the same default setting as the 313config_directory parameter, typically /etc/postfix or /usr/local/etc/postfix. 314 315You can override the default meta_directory location at compile time or after 316Postfix is built. To override the default location at compile time specify, for 317example: 318 319 % make makefiles meta_directory=/usr/libexec/postfix ... 320 321Here is a tip if you want to make a pathname dependent on the Postfix release 322version: the command "make makefiles name=value..." will replace the string 323MAIL_VERSION at the end of a configuration parameter value with the Postfix 324release version. Do not try to specify something like $mail_version on this 325command line. This produces inconsistent results with different versions of the 326make(1) command. 327 328You can override the meta_directory setting after Postfix is built, with "make 329install" or "make upgrade". 330 331 # make upgrade meta_directory=/usr/libexec/postfix ... 332 # make install meta_directory=/usr/libexec/postfix ... 333 334As with the command "make makefiles", the command "make install/upgrade 335name=value..." will replace the string MAIL_VERSION at the end of a 336configuration parameter value with the Postfix release version. Do not try to 337specify something like $mail_version on this command line. This produces 338inconsistent results with different versions of the make(1) command. 339 3404.4.4 Tips for distribution maintainers 341 342 * The shlib_directory parameter setting also provides the default directory 343 for database plugin files with a relative pathname in the file 344 dynamicmaps.cf. 345 346 * The meta_directory parameter specifies the location of the files 347 dynamicmaps.cf, postfix-files, and some multi-instance template files. The 348 meta_directory parameter has the same default value as the config_directory 349 parameter (typically, /etc/postfix or /usr/local/etc/postfix). For 350 backwards compatibility with Postfix 2.6 .. 2.11, specify "meta_directory = 351 $daemon_directory" in main.cf before installing or upgrading Postfix, or 352 specify "meta_directory = /path/name" on the "make makefiles", "make 353 install" or "make upgrade" command line. 354 355 * The configuration file dynamicmaps.cf will automatically include files 356 under the directory dynamicmaps.cf.d, just like the configuration file 357 postfix-files will automatically include files under the directory postfix- 358 files.d. Thanks to this, you can install or deinstall a database plugin 359 package without having to edit postfix-files or dynamicmaps.cf. Instead, 360 you give that plugin its own configuration files under dynamicmaps.cf.d and 361 postfix-files.d, and you add or remove those configuration files along with 362 the database plugin dynamically-linked object. 363 364 * Each configuration file under the directory dynamicmaps.cf.d must have the 365 same format as the configuration file dynamicmaps.cf. There is no 366 requirement that these configuration file *names* have a specific format. 367 368 * Each configuration file under the directory postfix-files.d must have the 369 same format as the configuration file postfix-files. There is no 370 requirement that these configuration file *names* have a specific format. 371 3724.5 - Building with optional features 373 374By default, Postfix builds as a mail system with relatively few bells and 375whistles. Support for third-party databases etc. must be configured when 376Postfix is compiled. The following documents describe how to build Postfix with 377support for optional features: 378 379 _____________________________________________________________ 380 |Optional feature |Document |Availability| 381 |__________________________________|_____________|____________| 382 |Berkeley DB database |DB_README |Postfix 1.0 | 383 |__________________________________|_____________|____________| 384 |LMDB database |LMDB_README |Postfix 2.11| 385 |__________________________________|_____________|____________| 386 |LDAP database |LDAP_README |Postfix 1.0 | 387 |__________________________________|_____________|____________| 388 |MySQL database |MYSQL_README |Postfix 1.0 | 389 |__________________________________|_____________|____________| 390 |Perl compatible regular expression|PCRE_README |Postfix 1.0 | 391 |__________________________________|_____________|____________| 392 |PostgreSQL database |PGSQL_README |Postfix 2.0 | 393 |__________________________________|_____________|____________| 394 |SASL authentication |SASL_README |Postfix 1.0 | 395 |__________________________________|_____________|____________| 396 |SQLite database |SQLITE_README|Postfix 2.8 | 397 |__________________________________|_____________|____________| 398 |STARTTLS session encryption |TLS_README |Postfix 2.2 | 399 |__________________________________|_____________|____________| 400 401Note: IP version 6 support is compiled into Postfix on operating systems that 402have IPv6 support. See the IPV6_README file for details. 403 4044.6 - Overriding built-in parameter default settings 405 4064.6.1 - Postfix 3.0 and later 407 408All Postfix configuration parameters can be changed by editing a Postfix 409configuration file, except for one: the parameter that specifies the location 410of Postfix configuration files. In order to build Postfix with a configuration 411directory other than /etc/postfix, use: 412 413 $ make makefiles config_directory=/some/where ...other arguments... 414 $ make 415 416The command "make makefiles name=value ..." will replace the string 417MAIL_VERSION at the end of a configuration parameter value with the Postfix 418release version. Do not try to specify something like $mail_version on this 419command line. This produces inconsistent results with different versions of the 420make(1) command. 421 422Parameters whose defaults can be specified in this way are listed below. See 423the postconf(5) manpage for a description (command: "nroff -man man/man5/ 424postconf.5 | less"). 425 426 __________________________________________ 427 |parameter name |typical default | 428 |_____________________|____________________| 429 |command_directory |/usr/sbin | 430 |_____________________|____________________| 431 |config_directory |/etc/postfix | 432 |_____________________|____________________| 433 |default_database_type|hash | 434 |_____________________|____________________| 435 |daemon_directory |/usr/libexec/postfix| 436 |_____________________|____________________| 437 |data_directory |/var/lib/postfix | 438 |_____________________|____________________| 439 |html_directory |no | 440 |_____________________|____________________| 441 |mail_spool_directory |/var/mail | 442 |_____________________|____________________| 443 |mailq_path |/usr/bin/mailq | 444 |_____________________|____________________| 445 |manpage_directory |/usr/local/man | 446 |_____________________|____________________| 447 |meta_directory |/etc/postfix | 448 |_____________________|____________________| 449 |newaliases_path |/usr/bin/newaliases | 450 |_____________________|____________________| 451 |openssl_path |openssl | 452 |_____________________|____________________| 453 |queue_directory |/var/spool/postfix | 454 |_____________________|____________________| 455 |readme_directory |no | 456 |_____________________|____________________| 457 |sendmail_path |/usr/sbin/sendmail | 458 |_____________________|____________________| 459 |shlib_directory |/usr/lib/postfix | 460 |_____________________|____________________| 461 4624.6.2 - All Postfix versions 463 464All Postfix configuration parameters can be changed by editing a Postfix 465configuration file, except for one: the parameter that specifies the location 466of Postfix configuration files. In order to build Postfix with a configuration 467directory other than /etc/postfix, use: 468 469 $ make makefiles CCARGS='-DDEF_CONFIG_DIR=\"/some/where\"' 470 $ make 471 472IMPORTANT: Be sure to get the quotes right. These details matter a lot. 473 474Parameters whose defaults can be specified in this way are listed below. See 475the postconf(5) manpage for a description (command: "nroff -man man/man5/ 476postconf.5 | less"). 477 478 ____________________________________________________________ 479 |Macro name |default value for |typical default | 480 |_________________|_____________________|____________________| 481 |DEF_COMMAND_DIR |command_directory |/usr/sbin | 482 |_________________|_____________________|____________________| 483 |DEF_CONFIG_DIR |config_directory |/etc/postfix | 484 |_________________|_____________________|____________________| 485 |DEF_DB_TYPE |default_database_type|hash | 486 |_________________|_____________________|____________________| 487 |DEF_DAEMON_DIR |daemon_directory |/usr/libexec/postfix| 488 |_________________|_____________________|____________________| 489 |DEF_DATA_DIR |data_directory |/var/lib/postfix | 490 |_________________|_____________________|____________________| 491 |DEF_MAILQ_PATH |mailq_path |/usr/bin/mailq | 492 |_________________|_____________________|____________________| 493 |DEF_HTML_DIR |html_directory |no | 494 |_________________|_____________________|____________________| 495 |DEF_MANPAGE_DIR |manpage_directory |/usr/local/man | 496 |_________________|_____________________|____________________| 497 |DEF_NEWALIAS_PATH|newaliases_path |/usr/bin/newaliases | 498 |_________________|_____________________|____________________| 499 |DEF_QUEUE_DIR |queue_directory |/var/spool/postfix | 500 |_________________|_____________________|____________________| 501 |DEF_README_DIR |readme_directory |no | 502 |_________________|_____________________|____________________| 503 |DEF_SENDMAIL_PATH|sendmail_path |/usr/sbin/sendmail | 504 |_________________|_____________________|____________________| 505 506Note: the data_directory parameter (for caches and pseudo-random numbers) was 507introduced with Postfix version 2.5. 508 5094.7 - Overriding other compile-time features 510 511The general method to override Postfix compile-time features is as follows: 512 513 $ make makefiles name=value name=value... 514 $ make 515 516The following is an extensive list of names and values. 517 518 _____________________________________________________________________________ 519|Name/Value |Description | 520|_______________________________|_____________________________________________| 521| |Specifies one or more non-default object | 522| |libraries. Postfix 3.0 and later specify some| 523| |of their database library dependencies with | 524|AUXLIBS="object_library..." |AUXLIBS_CDB, AUXLIBS_LDAP, AUXLIBS_LMDB, | 525| |AUXLIBS_MYSQL, AUXLIBS_PCRE, AUXLIBS_PGSQL, | 526| |AUXLIBS_SDBM, and AUXLIBS_SQLITE, | 527| |respectively. | 528|_______________________________|_____________________________________________| 529|CC=compiler_command |Specifies a non-default compiler. On many | 530| |systems, the default is gcc. | 531|_______________________________|_____________________________________________| 532| |Specifies non-default compiler arguments, for| 533|CCARGS="compiler_arguments..." |example, a non-default include directory. The| 534| |following directives turn off Postfix | 535| |features at compile time: | 536|_______________________________|_____________________________________________| 537|| |Do not build with Berkeley DB support. By | 538|| |default, Berkeley DB support is compiled in | 539||-DNO_DB |on platforms that are known to support this | 540|| |feature. If you override this, then you | 541|| |probably should also override DEF_DB_TYPE as | 542|| |described in section 4.6. | 543||______________________________|_____________________________________________| 544||-DNO_DNSSEC |Do not build with DNSSEC support, even if the| 545|| |resolver library appears to support it. | 546||______________________________|_____________________________________________| 547|| |Do not build with Solaris /dev/poll support. | 548||-DNO_DEVPOLL |By default, /dev/poll support is compiled in | 549|| |on Solaris versions that are known to support| 550|| |this feature. | 551||______________________________|_____________________________________________| 552|| |Do not build with Linux EPOLL support. By | 553||-DNO_EPOLL |default, EPOLL support is compiled in on | 554|| |platforms that are known to support this | 555|| |feature. | 556||______________________________|_____________________________________________| 557|| |Do not build with EAI (SMTPUTF8) support. By | 558||-DNO_EAI |default, EAI support is compiled in when the | 559|| |"icuuc" library and header files are found. | 560||______________________________|_____________________________________________| 561|| |Do not require support for C99 "inline" | 562|| |functions. Instead, implement argument | 563||-DNO_INLINE |typechecks for non-printf/scanf-like | 564|| |functions with ternary operators and | 565|| |unreachable code. | 566||______________________________|_____________________________________________| 567|| |Do not build with IPv6 support. By default, | 568|| |IPv6 support is compiled in on platforms that| 569|| |are known to have IPv6 support. Note: this | 570||-DNO_IPV6 |directive is for debugging And testing only. | 571|| |It is not guaranteed to work on all | 572|| |platforms. If you don't want IPv6 support, | 573|| |set "inet_protocols = ipv4" in main.cf. | 574||______________________________|_____________________________________________| 575|| |Do not build with FreeBSD / NetBSD / OpenBSD | 576||-DNO_KQUEUE |/ MacOSX KQUEUE support. By default, KQUEUE | 577|| |support is compiled in on platforms that are | 578|| |known to support it. | 579||______________________________|_____________________________________________| 580|| |Do not build with NIS or NISPLUS support. NIS| 581||-DNO_NIS |is not available on some recent Linux | 582|| |distributions. | 583||______________________________|_____________________________________________| 584|| |Do not build with NISPLUS support. NISPLUS is| 585||-DNO_NISPLUS |not available on some recent Solaris | 586|| |distributions. | 587||______________________________|_____________________________________________| 588|| |Do not build with PCRE support. By default, | 589||-DNO_PCRE |PCRE support is compiled in when the pcre- | 590|| |config utility is installed. | 591||______________________________|_____________________________________________| 592|| |Disable support for POSIX getpwnam_r/ | 593||-DNO_POSIX_GETPW_R |getpwuid_r. By default Postfix uses these | 594|| |where they are known to be available. | 595||______________________________|_____________________________________________| 596||-DNO_RES_NCALLS |Do not build with the threadsafe resolver(5) | 597|| |API (res_ninit() etc.). | 598||______________________________|_____________________________________________| 599|| |Use setjmp()/longjmp() instead of sigsetjmp | 600||-DNO_SIGSETJMP |()/siglongjmp(). By default, Postfix uses | 601|| |sigsetjmp()/siglongjmp() when they are known | 602|| |to be available. | 603||______________________________|_____________________________________________| 604|| |Use sprintf() instead of snprintf(). By | 605||-DNO_SNPRINTF |default, Postfix uses snprintf() except on | 606|| |ancient systems. | 607||______________________________|_____________________________________________| 608| |Specifies a non-default compiler debugging | 609|DEBUG=debug_level |level. The default is "-g". Specify DEBUG= to| 610| |turn off debugging. | 611|_______________________________|_____________________________________________| 612| |Specifies a non-default optimization level. | 613|OPT=optimization_level |The default is "-O". Specify OPT= to turn off| 614| |optimization. | 615|_______________________________|_____________________________________________| 616| |Specifies options for the postfix-install | 617|POSTFIX_INSTALL_OPTS=-option...|command, separated by whitespace. Currently, | 618| |the only supported option is "-keep-build- | 619| |mtime". | 620|_______________________________|_____________________________________________| 621| |Specifies non-default compiler options for | 622|SHLIB_CFLAGS=flags |building Postfix dynamically-linked libraries| 623| |and database plugins. The typical default is | 624| |"-fPIC". | 625|_______________________________|_____________________________________________| 626| |Specifies a non-default runpath for Postfix | 627|SHLIB_RPATH=rpath |dynamically-linked libraries. The typical | 628| |default is "'-Wl,-rpath,${SHLIB_DIR}'". | 629|_______________________________|_____________________________________________| 630| |Specifies a non-default suffix for Postfix | 631|SHLIB_SUFFIX=suffix |dynamically-linked libraries and database | 632| |plugins. The typical default is ".so". | 633|_______________________________|_____________________________________________| 634| |Specifies non-default compiler warning | 635|WARN="warning_flags..." |options for use when "make" is invoked in a | 636| |source subdirectory only. | 637|_______________________________|_____________________________________________| 638 6394.8 - Support for thousands of processes 640 641The number of connections that Postfix can manage simultaneously is limited by 642the number of processes that it can run. This number in turn is limited by the 643number of files and sockets that a single process can open. For example, the 644Postfix queue manager has a separate connection to each delivery process, and 645the anvil(8) server has one connection per smtpd(8) process. 646 647Postfix version 2.4 and later have no built-in limits on the number of open 648files or sockets, when compiled on systems that support one of the following: 649 650 * BSD kqueue(2) (FreeBSD 4.1, NetBSD 2.0, OpenBSD 2.9), 651 * Solaris 8 /dev/poll, 652 * Linux 2.6 epoll(4). 653 654With other Postfix versions or operating systems, the number of file 655descriptors per process is limited by the value of the FD_SETSIZE macro. If you 656expect to run more than 1000 mail delivery processes, you may need to override 657the definition of the FD_SETSIZE macro to make select() work correctly: 658 659 $ make makefiles CCARGS=-DFD_SETSIZE=2048 660 661Warning: the above has no effect on some Linux versions. Apparently, on these 662systems the FD_SETSIZE value can be changed only by using undocumented 663interfaces. Currently, that means including <bits/types.h> directly (which is 664not allowed) and overriding the __FD_SETSIZE macro. Beware, undocumented 665interfaces can change at any time and without warning. 666 667But wait, there is more: none of this will work unless the operating system is 668configured to handle thousands of connections. See the TUNING_README guide for 669examples of how to increase the number of open sockets or files. 670 6714.9 - Compiling Postfix, at last 672 673If the command 674 675 $ make 676 677is successful, then you can proceed to install Postfix (section 6). 678 679If the command produces compiler error messages, it may be time to search the 680web or to ask the postfix-users@postfix.org mailing list, but be sure to search 681the mailing list archives first. Some mailing list archives are linked from 682http://www.postfix.org/. 683 6845 - Porting Postfix to an unsupported system 685 686Each system type that Postfix knows is identified by a unique name. Examples: 687SUNOS5, FREEBSD4, and so on. When porting Postfix to a new system, the first 688step is to choose a SYSTEMTYPE name for the new system. You must use a name 689that includes at least the major version of the operating system (such as 690SUNOS4 or LINUX2), so that different releases of the same system can be 691supported without confusion. 692 693Add a case statement to the "makedefs" shell script in the source code top- 694level directory that recognizes the new system reliably, and that emits the 695right system-specific information. Be sure to make the code robust against user 696PATH settings; if the system offers multiple UNIX flavors (e.g. BSD and SYSV) 697be sure to build for the native flavor, instead of the emulated one. 698 699Add an "#ifdef SYSTEMTYPE" section to the central util/sys_defs.h include file. 700You may have to invent new feature macro names. Please choose sensible feature 701macro names such as HAS_DBM or FIONREAD_IN_SYS_FILIO_H. 702 703I strongly recommend against using "#ifdef SYSTEMTYPE" in individual source 704files. While this may look like the quickest solution, it will create a mess 705when newer versions of the same SYSTEMTYPE need to be supported. You're likely 706to end up placing "#ifdef" sections all over the source code again. 707 7086 - Installing the software after successful compilation 709 710This text describes how to install Postfix from source code. See the 711PACKAGE_README file if you are building a package for distribution to other 712systems. 713 7146.1 - Save existing Sendmail binaries 715 716IMPORTANT: if you are REPLACING an existing Sendmail installation with Postfix, 717you may need to keep the old sendmail program running for some time in order to 718flush the mail queue. 719 720 * Some systems implement a mail switch mechanism where different MTAs 721 (Postfix, Sendmail, etc.) can be installed at the same time, while only one 722 of them is actually being used. Examples of such switching mechanisms are 723 the FreeBSD mailwrapper(8) or the Linux mail switch. In this case you 724 should try to "flip" the switch to "Postfix" before installing Postfix. 725 726 * If your system has no mail switch mechanism, execute the following commands 727 (your sendmail, newaliases and mailq programs may be in a different place): 728 729 # mv /usr/sbin/sendmail /usr/sbin/sendmail.OFF 730 # mv /usr/bin/newaliases /usr/bin/newaliases.OFF 731 # mv /usr/bin/mailq /usr/bin/mailq.OFF 732 # chmod 755 /usr/sbin/sendmail.OFF /usr/bin/newaliases.OFF \ 733 /usr/bin/mailq.OFF 734 7356.2 - Create account and groups 736 737Before you install Postfix for the first time you need to create an account and 738a group: 739 740 * Create a user account "postfix" with a user id and group id that are not 741 used by any other user account. Preferably, this is an account that no-one 742 can log into. The account does not need an executable login shell, and 743 needs no existing home directory. My password and group file entries look 744 like this: 745 746 /etc/passwd: 747 postfix:*:12345:12345:postfix:/no/where:/no/shell 748 749 /etc/group: 750 postfix:*:12345: 751 752 Note: there should be no whitespace before "postfix:". 753 754 * Create a group "postdrop" with a group id that is not used by any other 755 user account. Not even by the postfix user account. My group file entry 756 looks like: 757 758 /etc/group: 759 postdrop:*:54321: 760 761 Note: there should be no whitespace before "postdrop:". 762 7636.3 - Install Postfix 764 765To install or upgrade Postfix from compiled source code, run one of the 766following commands as the super-user: 767 768 # make install (interactive version, first time install) 769 770 # make upgrade (non-interactive version, for upgrades) 771 772 * The interactive version ("make install") asks for pathnames for Postfix 773 data and program files, and stores your preferences in the main.cf file. If 774 you don't want Postfix to overwrite non-Postfix "sendmail", "mailq" and 775 "newaliases" files, specify pathnames that end in ".postfix". 776 777 * The non-interactive version ("make upgrade") needs the /etc/postfix/main.cf 778 file from a previous installation. If the file does not exist, use 779 interactive installation ("make install") instead. 780 781 * If you specify name=value arguments on the "make install" or "make upgrade" 782 command line, then these will take precedence over compiled-in default 783 settings or main.cf settings. 784 785 The command "make install/upgrade name=value ..." will replace the string 786 MAIL_VERSION at the end of a configuration parameter value with the Postfix 787 release version. Do not try to specify something like $mail_version on this 788 command line. This produces inconsistent results with different versions of 789 the make(1) command. 790 7916.4 - Configure Postfix 792 793Proceed to the section on how you wish to run Postfix on your particular 794machine: 795 796 * Send mail only, without changing an existing Sendmail installation (section 797 7). 798 799 * Send and receive mail via a virtual host interface, still without any 800 change to an existing Sendmail installation (section 8). 801 802 * Run Postfix instead of Sendmail (section 9). 803 8047 - Configuring Postfix to send mail only 805 806If you are going to use Postfix to send mail only, there is no need to change 807your existing sendmail setup. Instead, set up your mail user agent so that it 808calls the Postfix sendmail program directly. 809 810Follow the instructions in the "Mandatory configuration file edits" in section 81110, and review the "To chroot or not to chroot" text in section 11. 812 813You MUST comment out the "smtp inet" entry in /etc/postfix/master.cf, in order 814to avoid conflicts with the real sendmail. Put a "#" character in front of the 815line that defines the smtpd service: 816 817 /etc/postfix/master.cf: 818 #smtp inet n - n - - smtpd 819 820Start the Postfix system: 821 822 # postfix start 823 824or, if you feel nostalgic, use the Postfix sendmail command: 825 826 # sendmail -bd -qwhatever 827 828and watch your maillog file for any error messages. The pathname is /var/log/ 829maillog, /var/log/mail, /var/log/syslog, or something else. Typically, the 830pathname is defined in the /etc/syslog.conf file. 831 832 $ egrep '(reject|warning|error|fatal|panic):' /some/log/file 833 834Note: the most important error message is logged first. Later messages are not 835as useful. 836 837In order to inspect the mail queue, use one of the following commands: 838 839 $ mailq 840 841 $ sendmail -bp 842 843 $ postqueue -p 844 845See also the "Care and feeding" section 12 below. 846 8478 - Configuring Postfix to send and receive mail via virtual interface 848 849Alternatively, you can use the Postfix system to send AND receive mail while 850leaving your Sendmail setup intact, by running Postfix on a virtual interface 851address. Simply configure your mail user agent to directly invoke the Postfix 852sendmail program. 853 854To create a virtual network interface address, study your system ifconfig 855manual page. The command syntax could be any of: 856 857 # ifconfig le0:1 <address> netmask <mask> up 858 # ifconfig en0 alias <address> netmask 255.255.255.255 859 860In the /etc/postfix/main.cf file, I would specify 861 862 /etc/postfix/main.cf: 863 myhostname = virtual.host.tld 864 inet_interfaces = $myhostname 865 mydestination = $myhostname 866 867Follow the instructions in the "Mandatory configuration file edits" in section 86810, and review the "To chroot or not to chroot" text in section 11. 869 870Start the Postfix system: 871 872 # postfix start 873 874or, if you feel nostalgic, use the Postfix sendmail command: 875 876 # sendmail -bd -qwhatever 877 878and watch your maillog file for any error messages. The pathname is /var/log/ 879maillog, /var/log/mail, /var/log/syslog, or something else. Typically, the 880pathname is defined in the /etc/syslog.conf file. 881 882 $ egrep '(reject|warning|error|fatal|panic):' /some/log/file 883 884Note: the most important error message is logged first. Later messages are not 885as useful. 886 887In order to inspect the mail queue, use one of the following commands: 888 889 $ mailq 890 891 $ sendmail -bp 892 893 $ postqueue -p 894 895See also the "Care and feeding" section 12 below. 896 8979 - Running Postfix instead of Sendmail 898 899Prior to installing Postfix you should save any existing sendmail program files 900as described in section 6. Be sure to keep the old sendmail running for at 901least a couple days to flush any unsent mail. To do so, stop the sendmail 902daemon and restart it as: 903 904 # /usr/sbin/sendmail.OFF -q 905 906Note: this is old sendmail syntax. Newer versions use separate processes for 907mail submission and for running the queue. 908 909After you have visited the "Mandatory configuration file edits" section below, 910you can start the Postfix system with: 911 912 # postfix start 913 914or, if you feel nostalgic, use the Postfix sendmail command: 915 916 # sendmail -bd -qwhatever 917 918and watch your maillog file for any error messages. The pathname is /var/log/ 919maillog, /var/log/mail, /var/log/syslog, or something else. Typically, the 920pathname is defined in the /etc/syslog.conf file. 921 922 $ egrep '(reject|warning|error|fatal|panic):' /some/log/file 923 924Note: the most important error message is logged first. Later messages are not 925as useful. 926 927In order to inspect the mail queue, use one of the following commands: 928 929 $ mailq 930 931 $ sendmail -bp 932 933 $ postqueue -p 934 935See also the "Care and feeding" section 12 below. 936 93710 - Mandatory configuration file edits 938 939Note: the material covered in this section is covered in more detail in the 940BASIC_CONFIGURATION_README document. The information presented below is 941targeted at experienced system administrators. 942 94310.1 - Postfix configuration files 944 945By default, Postfix configuration files are in /etc/postfix. The two most 946important files are main.cf and master.cf; these files must be owned by root. 947Giving someone else write permission to main.cf or master.cf (or to their 948parent directories) means giving root privileges to that person. 949 950In /etc/postfix/main.cf, you will have to set up a minimal number of 951configuration parameters. Postfix configuration parameters resemble shell 952variables, with two important differences: the first one is that Postfix does 953not know about quotes like the UNIX shell does. 954 955You specify a configuration parameter as: 956 957 /etc/postfix/main.cf: 958 parameter = value 959 960and you use it by putting a "$" character in front of its name: 961 962 /etc/postfix/main.cf: 963 other_parameter = $parameter 964 965You can use $parameter before it is given a value (that is the second main 966difference with UNIX shell variables). The Postfix configuration language uses 967lazy evaluation, and does not look at a parameter value until it is needed at 968runtime. 969 970Whenever you make a change to the main.cf or master.cf file, execute the 971following command in order to refresh a running mail system: 972 973 # postfix reload 974 97510.2 - Default domain for unqualified addresses 976 977First of all, you must specify what domain will be appended to an unqualified 978address (i.e. an address without @domain.tld). The "myorigin" parameter 979defaults to the local hostname, but that is probably OK only for very small 980sites. 981 982Some examples (use only one): 983 984 /etc/postfix/main.cf: 985 myorigin = $myhostname (send mail as "user@$myhostname") 986 myorigin = $mydomain (send mail as "user@$mydomain") 987 98810.3 - What domains to receive locally 989 990Next you need to specify what mail addresses Postfix should deliver locally. 991 992Some examples (use only one): 993 994 /etc/postfix/main.cf: 995 mydestination = $myhostname, localhost.$mydomain, localhost 996 mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain 997 mydestination = $myhostname 998 999The first example is appropriate for a workstation, the second is appropriate 1000for the mailserver for an entire domain. The third example should be used when 1001running on a virtual host interface. 1002 100310.4 - Proxy/NAT interface addresses 1004 1005The proxy_interfaces parameter specifies all network addresses that Postfix 1006receives mail on by way of a proxy or network address translation unit. You may 1007specify symbolic hostnames instead of network addresses. 1008 1009IMPORTANT: You must specify your proxy/NAT external addresses when your system 1010is a backup MX host for other domains, otherwise mail delivery loops will 1011happen when the primary MX host is down. 1012 1013Example: host behind NAT box running a backup MX host. 1014 1015 /etc/postfix/main.cf: 1016 proxy_interfaces = 1.2.3.4 (the proxy/NAT external network address) 1017 101810.5 - What local clients to relay mail from 1019 1020If your machine is on an open network then you must specify what client IP 1021addresses are authorized to relay their mail through your machine into the 1022Internet. The default setting includes all subnetworks that the machine is 1023attached to. This may give relay permission to too many clients. My own 1024settings are: 1025 1026 /etc/postfix/main.cf: 1027 mynetworks = 168.100.189.0/28, 127.0.0.0/8 1028 102910.6 - What relay destinations to accept from strangers 1030 1031If your machine is on an open network then you must also specify whether 1032Postfix will forward mail from strangers. The default setting will forward mail 1033to all domains (and subdomains of) what is listed in $mydestination. This may 1034give relay permission for too many destinations. Recommended settings (use only 1035one): 1036 1037 /etc/postfix/main.cf: 1038 relay_domains = (do not forward mail from strangers) 1039 relay_domains = $mydomain (my domain and subdomains) 1040 relay_domains = $mydomain, other.domain.tld, ... 1041 104210.7 - Optional: configure a smart host for remote delivery 1043 1044If you're behind a firewall, you should set up a relayhost. If you can, specify 1045the organizational domain name so that Postfix can use DNS lookups, and so that 1046it can fall back to a secondary MX host when the primary MX host is down. 1047Otherwise just specify a hard-coded hostname. 1048 1049Some examples (use only one): 1050 1051 /etc/postfix/main.cf: 1052 relayhost = $mydomain 1053 relayhost = [mail.$mydomain] 1054 1055The form enclosed with [] eliminates DNS MX lookups. 1056 1057By default, the SMTP client will do DNS lookups even when you specify a relay 1058host. If your machine has no access to a DNS server, turn off SMTP client DNS 1059lookups like this: 1060 1061 /etc/postfix/main.cf: 1062 disable_dns_lookups = yes 1063 1064The STANDARD_CONFIGURATION_README file has more hints and tips for firewalled 1065and/or dial-up networks. 1066 106710.8 - Create the aliases database 1068 1069Postfix uses a Sendmail-compatible aliases(5) table to redirect mail for local 1070(8) recipients. Typically, this information is kept in two files: in a text 1071file /etc/aliases and in an indexed file /etc/aliases.db. The command "postconf 1072alias_maps" will tell you the exact location of the text file. 1073 1074First, be sure to update the text file with aliases for root, postmaster and 1075"postfix" that forward mail to a real person. Postfix has a sample aliases file 1076/etc/postfix/aliases that you can adapt to local conditions. 1077 1078 /etc/aliases: 1079 root: you 1080 postmaster: root 1081 postfix: root 1082 bin: root 1083 etcetera... 1084 1085Note: there should be no whitespace before the ":". 1086 1087Finally, build the indexed aliases file with one of the following commands: 1088 1089 # newaliases 1090 # sendmail -bi 1091 # postalias /etc/aliases (pathname is system dependent!) 1092 109311 - To chroot or not to chroot 1094 1095Postfix daemon processes can be configured (via master.cf) to run in a chroot 1096jail. The processes run at a fixed low privilege and with access only to the 1097Postfix queue directories (/var/spool/postfix). This provides a significant 1098barrier against intrusion. The barrier is not impenetrable, but every little 1099bit helps. 1100 1101With the exception of Postfix daemons that deliver mail locally and/or that 1102execute non-Postfix commands, every Postfix daemon can run chrooted. 1103 1104Sites with high security requirements should consider to chroot all daemons 1105that talk to the network: the smtp(8) and smtpd(8) processes, and perhaps also 1106the lmtp(8) client. The author's own porcupine.org mail server runs all daemons 1107chrooted that can be chrooted. 1108 1109The default /etc/postfix/master.cf file specifies that no Postfix daemon runs 1110chrooted. In order to enable chroot operation, edit the file /etc/postfix/ 1111master.cf. Instructions are in the file. 1112 1113Note that a chrooted daemon resolves all filenames relative to the Postfix 1114queue directory (/var/spool/postfix). For successful use of a chroot jail, most 1115UNIX systems require you to bring in some files or device nodes. The examples/ 1116chroot-setup directory in the source code distribution has a collection of 1117scripts that help you set up Postfix chroot environments on different operating 1118systems. 1119 1120Additionally, you almost certainly need to configure syslogd so that it listens 1121on a socket inside the Postfix queue directory. Examples for specific systems: 1122 1123FreeBSD: 1124 1125 # mkdir -p /var/spool/postfix/var/run 1126 # syslogd -l /var/spool/postfix/var/run/log 1127 1128Linux, OpenBSD: 1129 1130 # mkdir -p /var/spool/postfix/dev 1131 # syslogd -a /var/spool/postfix/dev/log 1132 113312 - Care and feeding of the Postfix system 1134 1135Postfix daemon processes run in the background, and log problems and normal 1136activity to the syslog daemon. The names of logfiles are specified in /etc/ 1137syslog.conf. At the very least you need something like: 1138 1139 /etc/syslog.conf: 1140 mail.err /dev/console 1141 mail.debug /var/log/maillog 1142 1143IMPORTANT: the syslogd will not create files. You must create them before 1144(re)starting syslogd. 1145 1146IMPORTANT: on Linux you need to put a "-" character before the pathname, e.g., 1147-/var/log/maillog, otherwise the syslogd will use more system resources than 1148Postfix does. 1149 1150Hopefully, the number of problems will be small, but it is a good idea to run 1151every night before the syslog files are rotated: 1152 1153 # postfix check 1154 # egrep '(reject|warning|error|fatal|panic):' /some/log/file 1155 1156 * The first line (postfix check) causes Postfix to report file permission/ 1157 ownership discrepancies. 1158 1159 * The second line looks for problem reports from the mail software, and 1160 reports how effective the relay and junk mail access blocks are. This may 1161 produce a lot of output. You will want to apply some postprocessing to 1162 eliminate uninteresting information. 1163 1164The DEBUG_README document describes the meaning of the "warning" etc. labels in 1165Postfix logging. 1166 1167