PGD-S
=====

..  Note::
   This architecture is for Postgres Distributed 6 only. If you require PGD 5 please use  :ref:`PGD-Always-ON <PGD-Always-ON>`  .

.. ::
   EDB Postgres Distributed 6 in a PGD Essential (PGD-S) configuration suitable for use in test and production.

This architecture requires an EDB subscription. All software is sourced
from :ref:`Configuring EDB Repos 2.0 repositories <Configuring EDB Repos 2.0 repositories>`  .

Cluster configuration
---------------------

Overview of configuration options
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

An example invocation of ``tpaexec configure`` for this architecture is
shown below.

.. code:: bash

   tpaexec configure ~/clusters/pgd-s \
       --architecture PGD-S
       --edb-postgres-extended 15 \
       --platform aws --instance-type t3.micro \
       --distribution Debian \

You can list all available options using the help command.

.. code:: bash

   tpaexec configure --architecture PGD-S --help

The table below describes the mandatory options for PGD-S and additional
important options. More detail on the options is provided in the
following section.

Mandatory Options
^^^^^^^^^^^^^^^^^

.. csv-table::
  :header: Options,Description
  :widths: 10,30
  :align: left
  :class: longtable

  `--architecture` (`-a`),Must be set to `PGD-S`
  Postgres flavour and version (e.g. `--postgresql 15`),A valid  :ref:`Postgres flavour and version<Postgres flavour and version>` .

Additional Options
^^^^^^^^^^^^^^^^^^

.. csv-table::
  :header: Options,Description,Behaviour if omitted
  :widths: 12,25,15
  :align: left
  :class: longtable

  `--platform`,"One of `aws`, `docker`, `bare`.",Defaults to `aws`.
  `--bdr-database`,The name of the database to be used for replication.,Defaults to `bdrdb`.
  `--layout`,`standard` or `near-far`,Defaults to `standard`
  `--add-subscriber-only-nodes`,"The number of subscriber-only nodes to add, up to 10.",Defaults to 0
  `--read-write-port`,The port for Connection Manager to listen on for read-write connections.,"Left empty in config.yml, allowing default of the postgres port + 1000"
  `--read-only-port`,The port for Connection Manager to listen on for read-only connections.,"Left empty in config.yml, allowing default of the read-write port + 1"
  `--http-port`,The port for Connection Manager to listen on for http api connections.,"Left empty in config.yml, allowing default of the read-write port + 2"
  `--use https`,Enable https for Connection Manager's http api,https is not enabled

More detail about PGD-S configuration
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

A PGD-S cluster has three data nodes. In the ``standard`` layout the
nodes are all in the same location; in the ``near-far`` layout two nodes
are in the primary location and the other is in a secondary location.
See the `PGDdocumentation <https://www.enterprisedb.com/docs/pgd/latest/essential-how-to/>`_ 

for more information about the two layouts.

The cluster also contains one barman node and up to 10 subscriber-only
nodes, controlled by the ``--add-subscriber-only-nodes`` parameter.
These are always in the primary location.

You may optionally specify ``--bdr-database dbname`` to set the name of
the database with BDR enabled (default: bdrdb).

You may also specify any of the options described by :ref:`Cluster configuration <Cluster configuration>`  .