postmulti(1)
NAME
postmulti - Postfix multi-instance manager
SYNOPSIS
Enabling multi-instance management: postmulti -e init [-v] Iterator mode: postmulti -l [-aRv] [-g group] [-i name] postmulti -p [-av] [-g group] [-i name] command... postmulti -x [-aRv] [-g group] [-i name] command... Life-cycle management: postmulti -e create [-av] [-g group] [-i name] [-G group] [-I name] [param=value ...] postmulti -e import [-av] [-g group] [-i name] [-G group] [-I name] [config_directory=/path] postmulti -e destroy [-v] -i name postmulti -e deport [-v] -i name postmulti -e enable [-v] -i name postmulti -e disable [-v] -i name postmulti -e assign [-v] -i name [-I name] [-G group]
DESCRIPTION
The postmulti(1) command allows a Postfix administrator to manage multiple Postfix instances on a single host. postmulti(1) implements two fundamental modes of operation. In iterator mode, it executes the same command for multiple Postfix instances. In life-cycle management mode, it adds or deletes one instance, or changes the multi-instance status of one instance. Each mode of operation has its own command syntax. For this reason, each mode is documented in separate sections below.
BACKGROUND
A multi-instance configuration consists of one primary Postfix instance, and one or more secondary instances whose configuration directory pathnames are recorded in the primary instance's main.cf file. Postfix instances share program files and documentation, but have their own configuration, queue and data directories. Currently, only the default Postfix instance can be used as primary instance in a multi-instance configuration. The postmulti(1) command does not currently support a -c option to select an alternative primary instance, and exits with a fatal error if the MAIL_CONFIG environment variable is set to a non-default configuration directory. See the MULTI_INSTANCE_README tutorial for a more detailed discussion of multi-instance management with postmulti(1).
ITERATOR MODE
In iterator mode, postmulti performs the same operation on all Postfix instances in turn. If multi-instance support is not enabled, the requested command is performed just for the primary instance. Iterator mode implements the following command options:
Instance selection
-a Perform the operation on all instances. This is the default.
-g group
Perform the operation only for members of the named group.
-i name
Perform the operation only for the instance with the specified
name. You can specify either the instance name or the absolute
pathname of the instance's configuration directory. Specify "-"
to select the primary Postfix instance.
-R Reverse the iteration order. This may be appropriate when
updating a multi-instance system, where "sink" instances are
started before "source" instances.
This option cannot be used with -p.
List mode
-l List Postfix instances with their instance name, instance group
name, enable/disable status and configuration directory.
Postfix-wrapper mode
-p Invoke postfix(1) to execute the specified command. This option implements the postfix-wrapper(5) interface. * With "start"-like commands, "postfix check" is executed for instances that are not enabled. The full list of commands is specified with the postmulti_start_commands parameter. * With "stop"-like commands, the iteration order is reversed, and disabled instances are skipped. The full list of commands is specified with the postmulti_stop_commands parameter. * With "reload" and other commands that require a started instance, disabled instances are skipped. The full list of commands is specified with the postmulti_control_commands parameter. * With "status" and other commands that don't require a started instance, the command is executed for all instances. The -p option can also be used interactively to start/stop/etc. a named instance or instance group. For example, to start just the instances in the group "msa", invoke postmulti(1) as follows: # postmulti -g msa -p start
Command mode
-x Execute the specified command for all Postfix instances. The
command runs with appropriate environment settings for
MAIL_CONFIG, command_directory, daemon_directory,
config_directory, queue_directory, data_directory,
multi_instance_name, multi_instance_group and
multi_instance_enable.
Other options
-v Enable verbose logging for debugging purposes. Multiple -v
options make the software increasingly verbose.
LIFE-CYCLE MANAGEMENT MODE
With the -e option postmulti(1) can be used to add or delete a Postfix instance, and to manage the multi-instance status of an existing instance. The following options are implemented:
Existing instance selection
-a When creating or importing an instance, place the new instance
at the front of the secondary instance list.
-g group
When creating or importing an instance, place the new instance
before the first secondary instance that is a member of the
specified group.
-i name
When creating or importing an instance, place the new instance
before the matching secondary instance.
With other life-cycle operations, apply the operation to the
named existing instance. Specify "-" to select the primary
Postfix instance.
New or existing instance name assignment
-I name
Assign the specified instance name to an existing instance,
newly-created instance, or imported instance. Instance names
other than "-" (which makes the instance "nameless") must start
with "postfix-". This restriction reduces the likelihood of
name collisions with system files.
-G group
Assign the specified group name to an existing instance or to a
newly created or imported instance.
Instance creation/deletion/status change
-e action
"Edit" managed instances. The following actions are supported:
init This command is required before postmulti(1) can be used
to manage Postfix instances. The "postmulti -e init"
command updates the primary instance's main.cf file by
setting:
multi_instance_wrapper =
${command_directory}/postmulti -p --
multi_instance_enable = yes
You can set these by other means if you prefer.
create Create a new Postfix instance and add it to the
multi_instance_directories parameter of the primary
instance. The "-I name" option is recommended to give
the instance a short name that is used to construct
default values for the private directories of the new
instance. The "-G group" option may be specified to
assign the instance to a group, otherwise, the new
instance is not a member of any groups.
The new instance main.cf is the stock main.cf with the
parameters that specify the locations of shared files
cloned from the primary instance. For "nameless"
instances, you should manually adjust "syslog_name" to
yield a unique "logtag" starting with "postfix-" that
will uniquely identify the instance in the mail logs. It
is simpler to assign the instance a short name with the
"-I name" option.
Optional "name=value" arguments specify the instance
config_directory, queue_directory and data_directory.
For example:
# postmulti -I postfix-mumble \
-G mygroup -e create \
config_directory=/my/config/dir \
queue_directory=/my/queue/dir \
data_directory=/my/data/dir
If any of these pathnames is not supplied, the program
attempts to generate the pathname by taking the
corresponding primary instance pathname, and by replacing
the last pathname component by the value of the -I
option.
If the instance configuration directory already exists,
and contains both a main.cf and master.cf file, create
will "import" the instance as-is. For existing instances,
create and import are identical.
import Import an existing instance into the list of instances
managed by the postmulti(1) multi-instance manager. This
adds the instance to the multi_instance_directories list
of the primary instance. If the "-I name" option is
provided it specifies the new name for the instance and
is used to define a default location for the instance
configuration directory (as with create above). The "-G
group" option may be used to assign the instance to a
group. Add a "config_directory=/path" argument to
override a default pathname based on "-I name".
destroy
Destroy a secondary Postfix instance. To be a candidate
for destruction an instance must be disabled, stopped and
its queue must not contain any messages. Attempts to
destroy the primary Postfix instance trigger a fatal
error, without destroying the instance.
The instance is removed from the primary instance main.cf
file's alternate_config_directories parameter and its
data, queue and configuration directories are cleaned of
files and directories created by the Postfix system. The
main.cf and master.cf files are removed from the
configuration directory even if they have been modified
since initial creation. Finally, the instance is
"deported" from the list of managed instances.
If other files are present in instance private
directories, the directories may not be fully removed, a
warning is logged to alert the administrator. It is
expected that an instance built using "fresh" directories
via the create action will be fully removed by the
destroy action (if first disabled). If the instance
configuration and queue directories are populated with
additional files (access and rewriting tables, chroot
jail content, etc.) the instance directories will not be
fully removed.
The destroy action triggers potentially dangerous file
removal operations. Make sure the instance's data, queue
and configuration directories are set correctly and do
not contain any valuable files.
deport Deport a secondary instance from the list of managed
instances. This deletes the instance configuration
directory from the primary instance's
multi_instance_directories list, but does not remove any
files or directories.
assign Assign a new instance name or a new group name to the
selected instance. Use "-G -" to specify "no group" and
"-I -" to specify "no name". If you choose to make an
instance "nameless", set a suitable syslog_name in the
corresponding main.cf file.
enable Mark the selected instance as enabled. This just sets the
multi_instance_enable parameter to "yes" in the
instance's main.cf file.
disable
Mark the selected instance as disabled. This means that
the instance will not be started etc. with "postfix
start", "postmulti -p start" and so on. The instance can
still be started etc. with "postfix -c config-directory
start".
Other options
-v Enable verbose logging for debugging purposes. Multiple -v
options make the software increasingly verbose.
ENVIRONMENT
The postmulti(1) command exports the following environment variables before executing the requested command for a given instance: MAIL_VERBOSE This is set when the -v command-line option is present. MAIL_CONFIG The location of the configuration directory of the instance.
CONFIGURATION PARAMETERS
config_directory (see 'postconf -d' output)
The default location of the Postfix main.cf and master.cf
configuration files.
daemon_directory (see 'postconf -d' output)
The directory with Postfix support programs and daemon programs.
import_environment (see 'postconf -d' output)
The list of environment parameters that a Postfix process will
import from a non-Postfix parent process.
multi_instance_directories (empty)
An optional list of non-default Postfix configuration
directories; these directories belong to additional Postfix
instances that share the Postfix executable files and
documentation with the default Postfix instance, and that are
started, stopped, etc., together with the default Postfix
instance.
multi_instance_group (empty)
The optional instance group name of this Postfix instance.
multi_instance_name (empty)
The optional instance name of this Postfix instance.
multi_instance_enable (no)
Allow this Postfix instance to be started, stopped, etc., by a
multi-instance manager.
postmulti_start_commands (start)
The postfix(1) commands that the postmulti(1) instance manager
treats as "start" commands.
postmulti_stop_commands (see 'postconf -d' output)
The postfix(1) commands that the postmulti(1) instance manager
treats as "stop" commands.
postmulti_control_commands (reload flush)
The postfix(1) commands that the postmulti(1) instance manager
treats as "control" commands, that operate on running instances.
syslog_facility (mail)
The syslog facility of Postfix logging.
syslog_name (see 'postconf -d' output)
The mail system name that is prepended to the process name in
syslog records, so that "smtpd" becomes, for example,
"postfix/smtpd".
Available in Postfix 3.0 and later:
meta_directory (see 'postconf -d' output)
The location of non-executable files that are shared among
multiple Postfix instances, such as postfix-files,
dynamicmaps.cf, and the multi-instance template files
main.cf.proto and master.cf.proto.
shlib_directory (see 'postconf -d' output)
The location of Postfix dynamically-linked libraries
(libpostfix-*.so), and the default location of Postfix database
plugins (postfix-*.so) that have a relative pathname in the
dynamicmaps.cf file.
FILES
$meta_directory/main.cf.proto, stock configuration file $meta_directory/master.cf.proto, stock configuration file $daemon_directory/postmulti-script, life-cycle helper program
SEE ALSO
postfix(1), Postfix control program postfix-wrapper(5), Postfix multi-instance API
README FILES
Use "postconf readme_directory" or "postconf html_directory" to locate this information. MULTI_INSTANCE_README, Postfix multi-instance management
HISTORY
The postmulti(1) command was introduced with Postfix version 2.6.
LICENSE
The Secure Mailer license must be distributed with this software.
AUTHOR(S)
Victor Duchovni
Morgan Stanley
Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA
POSTMULTI(1)
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