**master**
**********

The Cyrus IMAP master process.


Synopsis
========

   **master** [ **-C** *config-file* ] [ **-M** *alternate cyrus.conf* ]
       [ **-l** *listen queue* ] [ **-p** *pidfile* ]
       [ **-j** *janitor period* ] [ **-d** | **-D** ] [ **-L** *logfile* ]


Description
===========

**master** is the process that controls all of the Cyrus processes.
This process is responsible for creating all imapd, pop3d, lmtpd and
timsieved child processes. This process also performs scheduled
cleanup/maintenance.

If this process dies, then no new sessions will be started.

It kills itself and all child processes when it receives a SIGTERM.

**master** reads its configuration options out of the imapd.conf(5)
file unless specified otherwise by **-C**.


Options
=======

-C  alternate imapd.conf

   Use the specified configuration file *config-file* rather than the
   default imapd.conf(5).

-M  alternate cyrus.conf

   Specifies an alternate cyrus.conf for use by master.

-l  listen queue backlog

   Increase the listen queue backlog. By default, the listen queue is
   set to 32.   On systems with a high connection rate, it may be
   desirable to increase this value. refer to *listen(2)* for details.

-j  janitor full-sweeps per second

   Sets the number of times per second the janitor should sweep the
   entire child table.  Leave it at the default of 1 unless you have a
   really high fork rate (and you have not increased the child hash
   table size when you compiled Cyrus from its default of 10000
   entries).

-p  pidfile

   Use *pidfile* as the pidfile.  If not specified, defaults to
   "/var/run/master.pid"

-d

   Start in daemon mode (run in background and disconnect from
   controlling terminal).

-D

   Don’t close stdin/stdout/stderr. Primarily useful for debugging.
   Note that **-d** and **-D** cannot be used together; consider using
   **-L** instead.

-L  logfile

   Redirect stdout and stderr to the given *logfile*.


Configuration
=============

Upon execution, **master** reads its configuration information out of
the cyrus.conf(5) file, or an alternative if **-M** is used.

**master** rereads its configuration file when it receives a hangup
signal, SIGHUP.  Services and events may be added, deleted or modified
when the configuration file is reread.  Any active services removed
from the configuration file will be allowed to run until completion.
Services added or modified to listen on a privileged port may not be
able to bind the port, depending on your system configuration.  In
this case a full restart is needed.

**master** propagates the hangup signal, SIGHUP, to its child service
processes, so that they stop waiting for incoming connections and
exit, allowing them to be recycled.  This is useful to make services
take into account a new version of the imapd.conf(5) file.  Children
that are servicing a client connection when SIGHUP is received are
allowed to run until the client logouts before being recycled. It may
take a long time until the client logouts, so a log message is
generated for processes that have not been recycled within 30s.


Notes
=====

The environment variable **CYRUS_VERBOSE** can be set to log
additional debugging information. Setting the value to 1 results in
base level logging. Setting it higher results in more log messages
being generated.


Files
=====

/etc/cyrus.conf, /etc/imapd.conf, /var/run/master.pid


See Also
========

cyrus.conf(5), imapd.conf(5), imapd(8), pop3d(8), lmtpd(8),
timsieved(8), idled(8)
