What is repmgr?
repmgr is an open-source tool suite to manage replication and failover in a cluster of PostgreSQL servers. It enhances PostgreSQL's built-in hot-standby capabilities with tools to set up standby servers, monitor replication, and perform administrative tasks such as failover or manual switchover operations.
repmgr has provided advanced support for PostgreSQL's built-in replication mechanisms since they were introduced in 9.0, and repmgr 2.0 supports all PostgreSQL versions from 9.0 to 9.4. With further developments in replication functionality such as cascading replication, timeline switching and base backups via the replication protocol, the repmgr team has decided to use PostgreSQL 9.3 as the baseline version for repmgr 3.0, which is a substantial rewrite of the existing repmgr code and which will be developed to support future PostgreSQL versions.
Online documentation which describes the installation process and the most common usage patterns is available in the project GitHub repository.
Upgrading from repmgr 2.0 to repmgr 3.0 is quite straightforward; see the release notes for details.
Community and development
repmgr is free and open source software and is licensed under the GPL v3.
Contributions to repmgr are welcome. See the README.md file for information about how to contribute.