Thanks to Pacemaker and Corosync, PostgreSQL Automatic Failover (aka. PAF) is able to:
Thanks to Pacemaker and Corsync, you can easily build a SAFE and ROBUST cluster with:
Pacemaker is nowadays the industry reference for High Availability. In the same fashion than for Systemd, all Linux distributions moved (or are moving) to this unique Pacemaker+Corosync stack, removing all other existing high availability stacks (CMAN, RGManager, OpenAIS, …). It is able to detect failure on various services and automatically decide to failover the failing resource to another node when possible.
To be able to manage a specific service resource, Pacemaker interact with it through a so-called “Resource Agent”. Resource agents must comply to the OCF specification which define what they must implement (start, stop, promote, etc), how they should behave and inform Pacemaker of their results.
PostgreSQL Automatic Failover (aka. PAF) is a new Resource Agent dedicated to PostgreSQL. Its original wish is to keep a clear limit between the Pacemaker administration and the PostgreSQL one, to keep things simple, documented and yet powerful.
Once your PostgreSQL cluster built using internal streaming replication, PAF is able to expose to Pacemaker what is the current status of the PostgreSQL instance on each node: master, slave, stopped, catching up, etc. Should a failure occurs on the master, Pacemaker will try to recover it by default. Should the failure be non-recoverable, PAF allows the slaves to be able to elect the best of them (the closest one to the old master) and promote it as the new master. All of this thanks to the robust, feature-full and most importantly experienced project: Pacemaker.
For information about how to install, configure and manage this agent, as well as several Quick starts to help you getting started, see the documentation page.
PAF has been tested and works with PostgreSQL 9.3 and above, Pacemaker 1.1.x and above.
PAF is a free software licensed under the PostgreSQL License.