Chapter 10. Event Notifications

Each time repmgr or repmgrd perform a significant event, a record of that event is written into the repmgr.events table together with a timestamp, an indication of failure or success, and further details if appropriate. This is useful for gaining an overview of events affecting the replication cluster. However note that this table has advisory character and should be used in combination with the repmgr and PostgreSQL logs to obtain details of any events.

Example output after a primary was registered and a standby cloned and registered:

    repmgr=# SELECT * from repmgr.events ;
     node_id |      event       | successful |        event_timestamp        |                                       details
    ---------+------------------+------------+-------------------------------+-------------------------------------------------------------------------------------
           1 | primary_register | t          | 2016-01-08 15:04:39.781733+09 |
           2 | standby_clone    | t          | 2016-01-08 15:04:49.530001+09 | Cloned from host 'repmgr_node1', port 5432; backup method: pg_basebackup; --force: N
           2 | standby_register | t          | 2016-01-08 15:04:50.621292+09 |
    (3 rows)

Alternatively, use repmgr cluster event to output a formatted list of events.

Additionally, event notifications can be passed to a user-defined program or script which can take further action, e.g. send email notifications. This is done by setting the event_notification_command parameter in repmgr.conf.

This parameter accepts the following format placeholders:

%n

node ID

%e

event type

%t

success (1 or 0)

%t

timestamp

%d

details

The values provided for %t and %d will probably contain spaces, so should be quoted in the provided command configuration, e.g.:

    event_notification_command='/path/to/some/script %n %e %s "%t" "%d"'
  

Additionally the following format placeholders are available for the event type bdr_failover and optionally bdr_recovery:

%c

conninfo string of the next available node

%a

name of the next available node

These should always be quoted.

By default, all notification types will be passed to the designated script; the notification types can be filtered to explicitly named ones:

Note that under some circumstances (e.g. when no replication cluster primary could be located), it will not be possible to write an entry into the repmgr.events table, in which case executing a script via event_notification_command can serve as a fallback by generating some form of notification.