postalias

postalias - Postfix alias database maintenance

Beschreibung

The postalias(1) command creates or queries one or more Postfix alias databases, or updates an existing one. The input and output file formats are expected to be compatible with Sendmail version 8, and are expected to be suitable for the 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.

Syntax

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

Parameter

fail A table that reliably fails all requests. The lookup table 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 databases. 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.When no file_type is specified, the software uses the database type specified via the default_database_type configuration parameter. The default value for this parameter depends on the host environment.

Option	Beschreibung
file_type	The database type. To find out what types are supported, use the "postconf -m" command. 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.
file_name	The name of the alias database source file when creating a database.

Optionen

Option	Beschreibung
-c config_dir	Read the main.cf configuration file in the named directory instead 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.
-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 default 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 options make the software increasingly verbose.
-w	When updating a table, do not complain about attempts to update existing entries, and ignore those attempts.

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