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PostgreSQL Replication slot

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Configuration

You can create a replication slot like this:
postgres=# SELECT * FROM pg_create_physical_replication_slot('node_a_slot');
  slot_name  | xlog_position
-------------+---------------
 node_a_slot |

postgres=# SELECT * FROM pg_replication_slots;
  slot_name  | slot_type | datoid | database | active | xmin | restart_lsn | confirmed_flush_lsn
-------------+-----------+--------+----------+--------+------+-------------+---------------------
 node_a_slot | physical  |        |          | f      |      |             |
(1 row)
To configure the standby to use this slot, primary_slot_name should be configured in the standby's recovery.conf. Here is a simple example:
standby_mode = 'on'
primary_conninfo = 'host=192.168.1.50 port=5432 user=foo password=foopass'
primary_slot_name = 'node_a_slot'

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