tpaexec switchover
==================

The ``tpaexec switchover`` command performs a controlled switchover
between a primary and a replica in a :ref:`M1 <M1>`  . After you run this
command, the selected replica is promoted to be the new primary, the
former primary becomes a new replica, and any other replicas in the
cluster will be reconfigured to follow the new primary.

The command checks that the cluster is healthy before switching roles,
and is designed to be run without having to shut down any repmgr
services beforehand.

(This is equivalent to running ``repmgr standby switchover`` with the
``--siblings-follow`` option.)

Example
-------

This command will make ``replicaname`` be the new primary in
``~/clusters/speedy`` :

.. code:: bash

   tpaexec switchover ~/clusters/speedy replicaname

Architecture options
--------------------

This command is applicable only to :ref:`M1 <M1>` 

that have a single writable primary instance and one or more read-only
replicas.

For BDR-Always-ON clusters, use the :ref:`BDR/HAProxy server pool management <BDR/HAProxy server pool management>`  to perform maintenance
on PGD instances.

Repmgr redirect pgbouncer
-------------------------

When using repmgr as failover manager, pgbouncer as connection pooler
and setting ``repmgr_redirect_pgbouncer: true`` , switchover command
ensures that the pgbouncer instances are redirected to the new primary
node.

..  Note Revert to initial primary::
   In case you already switched over to a different primary, you can specify `revert_redirect: true`  on the command that will switch back to the initial primary to make use of the initial pgbouncer config file instead of regenerating it. TPA saves the initial state of this config file as `pgbouncer.databases.ini.orig`  during a switchover and can revert to it when going back to the initial primary

.. code:: bash

           # switchover to a replica
           tpaexec switchover <cluster_name> <replica_name>
           # revert to initial primary
           tpaexec switchover <cluster_name> <initial_primary_name> -e"revert_redirect=true"