POSTALIAS(1)                General Commands Manual               POSTALIAS(1)

NAME
       postalias - Postfix alias database maintenance

SYNOPSIS
       postalias [-Nfijnoprsuvw] [-c config_dir] [-d key] [-q key]
               [file_type:]file_name ...

DESCRIPTION
       The  postalias(1)  command creates or queries one or more Postfix alias
       databases, or updates an existing one. The input and output  file  for‐
       mats are expected to be compatible with Sendmail version 8, and are ex‐
       pected to be suitable for use as NIS alias maps.

       If  the  result  files  do not exist they will be created with the same
       group and other read permissions as their source file.

       While a database update is in progress, signal delivery  is  postponed,
       and  an  exclusive, advisory, lock is placed on the entire database, in
       order to avoid surprises in spectator processes.

       The format of Postfix alias input files is described in aliases(5).

       By default the lookup key is mapped to lowercase to  make  the  lookups
       case insensitive; as of Postfix 2.3 this case folding happens only with
       tables whose lookup keys are fixed-case strings such as btree:, dbm: or
       hash:. With earlier versions, the lookup key is folded even with tables
       where  a lookup field can match both upper and lower case text, such as
       regexp: and pcre:. This resulted in loss of  information  with  $number
       substitutions.

       Options:

       -c config_dir
              Read  the  main.cf configuration file in the named directory in‐
              stead of the default configuration directory.

       -d key Search the specified maps for key and remove one entry per  map.
              The  exit  status  is  zero  when  the requested information was
              found.

              If a key value of - is specified, the program reads  key  values
              from  the standard input stream. The exit status is zero when at
              least one of the requested keys was found.

       -f     Do not fold the lookup key  to  lower  case  while  creating  or
              querying a table.

              With  Postfix  version  2.3 and later, this option has no effect
              for regular expression tables. There, case folding is controlled
              by appending a flag to a pattern.

       -i     Incremental mode. Read entries from standard input  and  do  not
              truncate  an existing database. By default, postalias(1) creates
              a new database from the entries in file_name.

       -j     JSON output. Format the output from -q and  -s  as  one  {"key":
              "value"} object per line.

              This feature is available in Postfix version 3.11 and later.

       -N     Include  the  terminating  null character that terminates lookup
              keys and values. By default, postalias(1) does whatever  is  the
              default for the host operating system.

       -n     Don't  include  the  terminating  null character that terminates
              lookup keys and values. By default, postalias(1)  does  whatever
              is the default for the host operating system.

       -o     Do  not release root privileges when processing a non-root input
              file. By default, postalias(1) drops root privileges and runs as
              the source file owner instead.

       -p     Do not inherit the file access permissions from the  input  file
              when  creating  a new file.  Instead, create a new file with de‐
              fault access permissions (mode 0644).

       -q key Search the specified maps for key  and  write  the  first  value
              found  to  the  standard  output stream. The exit status is zero
              when the requested information was found.

              Note: this performs a single query with the  key  as  specified,
              and  does  not make iterative queries with substrings of the key
              as described in the aliases(5) manual page.

              If a key value of - is specified, the program reads  key  values
              from the standard input stream and writes one line of key: value
              output for each key that was found. The exit status is zero when
              at least one of the requested keys was found.

       -r     When  updating a table, do not complain about attempts to update
              existing entries, and make those updates anyway.

       -s     Retrieve all database elements, and write one line of key: value
              output for each element. The elements are  printed  in  database
              order,  which  is not necessarily the same as the original input
              order.  This feature is available in  Postfix  version  2.2  and
              later, and is not available for all database types.

       -u     Disable  UTF-8 support. UTF-8 support is enabled by default when
              "smtputf8_enable = yes". It requires that keys  and  values  are
              valid UTF-8 strings.

       -v     Enable  verbose  logging for debugging purposes. Multiple -v op‐
              tions make the software increasingly verbose.

       -w     When updating a table, do not complain about attempts to  update
              existing entries, and ignore those attempts.

       Arguments:

       file_type
              The database type. To find out what types are supported, use the
              "postconf -m" command.

              When  no  file_type is specified, the software uses the database
              type specified via the default_database_type configuration para‐
              meter.  The default value for this parameter depends on the host
              environment.

              The postalias(1) command can query any supported file type,  but
              it can create only the following file types:

              btree  The  output is a btree file, named file_name.db.  This is
                     available on systems with support for db databases.

              cdb    The output is one  file  named  file_name.cdb.   This  is
                     available on systems with support for cdb databases.

              dbm    The output consists of two files, named file_name.pag and
                     file_name.dir.  This is available on systems with support
                     for dbm databases.

              fail   A  table that reliably fails all requests. The lookup ta‐
                     ble name is used for logging only. This table  exists  to
                     simplify Postfix error tests.

              hash   The output is a hashed file, named file_name.db.  This is
                     available on systems with support for db databases.

              lmdb   The  output  is a btree-based file, named file_name.lmdb.
                     lmdb supports concurrent writes and reads from  different
                     processes,  unlike  other  supported  file-based  tables.
                     This is available on systems with support for lmdb  data‐
                     bases.

              sdbm   The output consists of two files, named file_name.pag and
                     file_name.dir.  This is available on systems with support
                     for sdbm databases.

       file_name
              The name of the alias database source file when creating a data‐
              base.

DIAGNOSTICS
       Problems  are  logged to the standard error stream and to syslogd(8) or
       postlogd(8). No output means that no problems were detected.  Duplicate
       entries are skipped and are flagged with a warning.

       postalias(1)  terminates  with zero exit status in case of success (in‐
       cluding successful "postalias -q" lookup) and terminates with  non-zero
       exit status in case of failure.

ENVIRONMENT
       MAIL_CONFIG
              Directory with Postfix configuration files.

       MAIL_VERBOSE
              Enable verbose logging for debugging purposes.

CONFIGURATION PARAMETERS
       The  following  main.cf parameters are especially relevant to this pro‐
       gram.

       The text below provides only a parameter summary. See  postconf(5)  for
       more details including examples.

       alias_database (see 'postconf -d' output)
              The  alias databases for local(8) delivery that are updated with
              "newaliases" or with "sendmail -bi".

       config_directory (see 'postconf -d' output)
              The default location of the Postfix main.cf and  master.cf  con‐
              figuration files.

       berkeley_db_create_buffer_size (16777216)
              The  per-table I/O buffer size for programs that create Berkeley
              DB hash or btree tables.

       berkeley_db_read_buffer_size (131072)
              The per-table I/O buffer size for programs that read Berkeley DB
              hash or btree tables.

       default_database_type (see 'postconf -d' output)
              The default database type for use in newaliases(1), postalias(1)
              and postmap(1) commands.

       import_environment (see 'postconf -d' output)
              The list of environment  variables  that  a  privileged  Postfix
              process  will  import  from  a  non-Postfix  parent  process, or
              name=value environment overrides.

       smtputf8_enable (yes)
              Enable preliminary SMTPUTF8 support for the protocols  described
              in RFC 6531, RFC 6532, and RFC 6533.

       syslog_facility (mail)
              The syslog facility of Postfix logging.

       syslog_name (see 'postconf -d' output)
              A  prefix  that  is  prepended  to  the  process  name in syslog
              records, so that, for example, "smtpd" becomes "prefix/smtpd".

       Available in Postfix 2.11 and later:

       lmdb_map_size (16777216)
              The initial OpenLDAP LMDB database size limit in bytes.

STANDARDS
       RFC 822 (ARPA Internet Text Messages)

SEE ALSO
       aliases(5), format of alias database input file.
       local(8), Postfix local delivery agent.
       postconf(1), supported database types
       postconf(5), configuration parameters
       postmap(1), create/update/query lookup tables
       newaliases(1), Sendmail compatibility interface.
       postlogd(8), Postfix logging
       syslogd(8), system logging

README FILES
       DATABASE_README, Postfix lookup table overview

LICENSE
       The Secure Mailer license must be distributed with this software.

AUTHOR(S)
       Wietse Venema
       IBM T.J. Watson Research
       P.O. Box 704
       Yorktown Heights, NY 10598, USA

       Wietse Venema
       Google, Inc.
       111 8th Avenue
       New York, NY 10011, USA

                                                                  POSTALIAS(1)