Nerd Press - News Archive [October 6, 2016]

	repmgr 3.2 released

2ndQuadrant is proud to announce the release of repmgr version 3.2 which includes new features for Barman, replication cluster managing, standby cloning improvements, better integration of OS-level server commands, and other minor commands and improvements.

This release leverages improvements included with PostgreSQL 9.6 to provide support for switchover, a common administrative task where the roles of primary and standby server are swapped in a controlled manner to facilitate software and hardware maintenance.??

Note: repmgr 3.2 supports PostgreSQL 9.3 and later only.

What is repmgr?

repmgr is an open source package which greatly simplifies the process of setting up and managing replication using streaming replication within a cluster of PostgreSQL servers. Taking advantage of features introduced in PostgreSQL releases since 9.3, repmgr builds on PostgreSQL's core functionality to provide a smooth, user-friendly way of working with the complexities of replication and failover management in high-availability environments.

New features in repmgr 3.2

Barman Support

repmgr 3.2 provides enhanced integration with 2ndQuadrant's Barman backup and recovery manager. In particular, it is now possible to clone a standby from a Barman archive, rather than directly from a running database server. This means the server is not subjected to the I/O load caused by a backup, and there's no need to manage WAL retention on the database server. The standby can also use the Barman archive as a fallback source of WAL in case streaming replication is interrupted.??

Replication Cluster Monitoring

Usually, when working with more complex replication clusters spread over multiple locations, gaining an overview of connection status between nodes can be a tedious and time-consuming process. repmgr 3.2 provides two new commands which help with this, expanding the existing “repmgr cluster show”. You can read in depth about these commands in the README file.

Standby Cloning Improvements

In addition to the ability to clone directly from a Barman archive, various other improvements have been made to the standby cloning process. In particular, by default password-less SSH connection between servers is now optional and only needs to be provided for specific features.

Better Integration of OS Level Server Commands

By default, repmgr.conf will use PostgreSQL's standard pg_ctl utility to control a running PostgreSQL server. However, it may be better to use the operating system's service management system. To specify which service control commands are used, the following repmgr.conf configuration settings are available:?

service_start_command
service_stop_command
service_restart_command
service_reload_command
service_promote_command

Read the formal release notes for information on other new commands, options, and improvements included in this release as well as upgrade instructions.

2ndQuadrant provides professional support services for repmgr — for more information, visit https://2ndquadrant.com/en/support/support-postgresql/.