NAME

       pg_createcluster - create a new PostgreSQL cluster

SYNOPSIS

       pg_createcluster [options] version name [-- initdb options]

DESCRIPTION

       pg_createcluster creates a new PostgreSQL server cluster (i. e. a collection of databases served by a
       postmaster(1) instance) and integrates it into the multi-version/multi-cluster architecture of the
       postgresql-common package.

       Every cluster is uniquely identified by its version and name. The name can be arbitrary. The default
       cluster that is created on installation of a server package is main. However, you might wish to create
       other clusters for testing, with other superusers, a cluster for each user on a shared server, etc.
       pg_createcluster will abort with an error if you try to create a cluster with a name that already exists
       for that version.

       Given a major PostgreSQL version (like "8.2" or "8.3") and a cluster name, it creates the necessary
       configuration files in /etc/postgresql/version/name/; in particular these are postgresql.conf,
       pg_ident.conf, pg_hba.conf, a postgresql-common specific configuration file start.conf (see STARTUP
       CONTROL below), pg_ctl.conf, and a symbolic link log which points to the log file (by default,
       /var/log/postgresql/postgresql-version-name.log).

       postgresql.conf is automatically adapted to use the next available port, i.  e. the first port (starting
       from 5432) which is not yet used by an already existing cluster.

       If the data directory does not yet exist, PostgreSQL's initdb(1) command is used to generate a new
       cluster structure. If the data directory already exists, it is integrated into the postgresql-common
       structure by moving the configuration file and setting the data_directory option. Please note that this
       only works for data directories which were created directly with initdb, i.  e. all the configuration
       files (postgresql.conf etc.) must be present in the data directory.

       If a custom socket directory is given and it does not exist, it is created.

       If the log file does not exist, it is created. In any case the permissions are adjusted to allow write
       access to the cluster owner. Please note that postgresql.conf can be customized to specify log_directory
       and/or log_filename; if at least one of these options is present, then the symbolic link log in the
       cluster configuration directory is ignored.

       If the default snakeoil SSL certificate exists (/etc/ssl/certs/ssl-cert-snakeoil.pem and
       /etc/ssl/private/ssl-cert-snakeoil.key), and the postgres user is in the ssl-cert Unix group,
       pg_createcluster configures the cluster to use this certificate, and enables SSL. Therefore all clusters
       will use the same SSL certificate by default. For versions up to 9.1, symlinks in the data directory will
       be created (server.crt and server.key); for 9.2 and later, the appropriate postgresql.conf options will
       be set (ssl_cert_file and ssl_key_file). Of course you can replace this with a cluster specific
       certificate. Similary for /etc/postgresql-common/root.crt and /etc/postgresql-common/root.crl, these
       files will be configured as client certificate CA and revocation list, when present. (root.crt is
       initially a placeholder that will only be used if real certificates are added to the file.)

OPTIONS

       -u user, --user=user
           Set the user who owns the cluster and becomes the database superuser to the given name or uid.  By
           default, this is the user postgres.  A cluster must not be owned by root.

       -g group, --group=group
           Change the group of the cluster related data files. By default this will be the primary group of the
           database owner.

       -d dir, --datadir=dir
           Explicitly set the data directory path, which is used to store all the actual databases and tables.
           This will become quite big (easily in the order of five times the amount of actual data stored in the
           cluster). Defaults to /var/lib/postgresql/version/cluster.

       -s dir, --socketdir=dir
           Explicitly set the directory where the postmaster(1) server stores the Unix socket for local
           connections. Defaults to /var/run/postgresql/ for clusters owned by the user postgres, and /tmp for
           clusters owned by other users.  Please be aware that /tmp is an unsafe directory since everybody can
           create a socket there and impersonate the database server. If the given directory does not exist, it
           is created with appropriate permissions.

       -l path, --logfile=path
           Explicitly set the path for the postmaster(1) server log file. Defaults to
           /var/log/postgresql/postgresql-version-cluster.log.

       --locale=locale
           Set the default locale for the database cluster. If this option is not specified, the locale is
           inherited from the environment that pg_createcluster runs in.

       --lc-collate=locale
       --lc-ctype=locale
       --lc-messages=locale
       --lc-monetary=locale
       --lc-numeric=locale
       --lc-time=locale
           Like --locale, but only sets the locale in the specified category.

       -e encoding, --encoding=encoding
           Select the encoding of the template database. This will also be the default encoding of any database
           you create later, unless you override it there. The default is derived from the locale, or SQL_ASCII
           if that does not work.  The character sets supported by the PostgreSQL server are described in the
           documentation.

           Note: It is not recommended to set this option directly! Set the locale instead.

       -p port, --port=port
           Select the port the new cluster listens on (for the Unix socket and the TCP port); this must be a
           number between 1024 and 65535, since PostgreSQL does not run as root and thus needs an unprivileged
           port number. By default the next free port starting from 5432 is assigned.

       --start
           Immediately start a server for the cluster after creating it (i. e. call pg_ctlcluster version
           cluster start on it). By default, the cluster is not started.

       --start-conf=auto|manual|disabled
           Set the initial value in the start.conf configuration file. See STARTUP CONTROL below. By default,
           auto is used, which means that the cluster is handled by /etc/init.d/postgresql, i. e. starts and
           stops automatically on system boot.

       -o guc=value, --pgoption guc=value
           Configuration option to set in the new postgresql.conf file.

       --createclusterconf=file
           Alternative createcluster.conf file to use. Default is /etc/postgresql-common/createcluster.conf (or
           $PGSYSCONFDIR/createcluster.conf).

       --environment=file
           Alternative default environment file to use. Default is /etc/postgresql-common/environment (or
           $PGSYSCONFDIR/environment).  If the file is missing, a placeholder string is used.  %v and %c are
           replaced; see DEFAULT VALUES below.

       -- initdb options
           Options passed directly to initdb(1).

           Per default, pg_createcluster will update the pg_hba.conf file generated by initdb to use peer
           authentication on local (unix) connections, and md5 on TCP (host) connections. If explicit
           authentication config is included here (-A, --auth, --auth-host, --auth-local), the pg_hba.conf file
           will be left untouched.

STARTUP CONTROL

       The start.conf file in the cluster configuration directory controls the start/stop behavior of that
       cluster's postmaster process. The file can contain comment lines (started with '#'), empty lines, and
       must have exactly one line with one of the following keywords:

       auto
           The postmaster process is started/stopped automatically in the init script.  This is also the default
           if the file is missing.

       manual
           The postmaster process is not handled by the init script, but manually controlling the cluster with
           pg_ctlcluster(1) is permitted.

       disabled
           Neither the init script nor pg_ctlcluster(1) are permitted to start/stop the cluster. Please be aware
           that this will not stop the cluster owner from calling lower level tools to control the postmaster
           process; this option is only meant to prevent accidents during maintenance, not more.

       The pg_ctl.conf file in the cluster configuration directory can contain additional options passed to
       pg_ctl of that cluster.

DEFAULT VALUES

       Some default values used by pg_createcluster can be modified in
       /etc/postgresql-common/createcluster.conf:

       create_main_cluster (Default: true)
           Create a main cluster when a new postgresql-x.y server package is installed.

       start_conf (Default: auto)
           Default start.conf value to use.

       In the following options, occurrences of %v are replaced by the major version number, and %c by the
       cluster name. Use %% for a literal %.

       data_directory (Default: /var/lib/postgresql/%v/%c)
           Default data directory.

       xlogdir (Default: unset)
           Default directory for transaction logs. When used, initdb will create a symlink from pg_xlog in the
           data directory to this location. Unset by default, i.e. pg_xlog is remains in the data directory.

       initdb_options (Default: unset)
           Other options to pass to initdb.

       other options (Default: none)
           All other options listed are copied into the new cluster's postgresql.conf, e.g.:

               listen_addresses = '*'
               log_line_prefix = '%%t '

SEE ALSO

       initdb(1), pg_ctlcluster(8), pg_lsclusters(1), pg_wrapper(1)

AUTHORS

       Martin Pitt <mpitt@debian.org>, Christoph Berg <myon@debian.org>