repmgr 3.1.3 released
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 since PostgreSQL 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.
repmgr consists of two core tools - the repmgr command line interface, which provides functionality for adminstering replication such as cloning standby servers, and repmgrd, a background daemon which monitors nodes in a replication cluster and provides automatic failover support.
The latest repmgr major version, 3.1, leverages improvements included with PostgreSQL 9.5 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 that repmgr 3.1 supports PostgreSQL 9.3 and later only.
2ndQuadrant provides professional support services for repmgr - see our website for details.
Changes in release 3.1.3
repmgrd is now able to monitor a standby which is catching up to the master by replaying archived WAL. Additionally repmgrd's behaviour during a failover situation, where the original master reappears during standby promotion, has been improved.
Various smaller improvements and bugfixes have been made, including handling rsync errors caused by files disappearing; these should no longer cause STANDBY CLONE to fail.
Beginning with repmgr 3.1.3, 2ndQuadrant provides a dedicated yum repository for repmgr releases so that users of Red Hat-derived distributions can obtain the latest rpm packages without delay.
Upgrading from older repmgr versions
Upgrading from repmgr 3.1.2
repmgr 3.1.3 can simply be installed in placed of the existing repmgr 3.1.2 version.
If repmgrd is running, stop and restart the service to ensure it is running with the current repmgr version.
Upgrading from repmgr 3.1.1 or 3.1
To upgrade from repmgr 3.1.1 or repmgr 3.1 version, install repmgr 3.1.3 from your operating system's packaging system or from source, then perform following tasks:
- Run the provided repmgr database upgrade script, repmgr3.1.1_repmgr3.1.2.sql. This makes a small modification to the repl_nodes table's foreign key definition.
- If repmgrd is running, stop and restart the service to ensure it is running with the current repmgr version.
Upgrading from repmgr 3.0
repmgr 3.1.3 is a drop-in replacement for an existing repmgr 3.0 installation. It should be installed first, either from your operating system's packaging system or from source, then following tasks performed:
- Run the provided repmgr database upgrade script, sql/repmgr3.0_repmgr3.1.sql. This introduces one new convenience view, repl_show_nodes, but otherwise no changes have been made to repmgr's metadata schema.
- Run the provided repmgr database upgrade script, repmgr3.1.1_repmgr3.1.2.sql. This makes a small modification to the repl_nodes table's foreign key definition.
- If repmgrd is running, stop and restart the service to ensure it is running with the current repmgr version.
Upgrading from repmgr 2.0
repmgr 3.1.3 can replace an existing repmgr 2.0 installation. It should be installed first, either from your operating system's packaging system or from source, then following tasks performed:
- If repmgrd is running, stop the service.
-
Run the provided repmgr database upgrade script, sql/repmgr2_repmgr3.sql,
which is required to expand the
repl_nodes
table. - Run the provided repmgr database upgrade script, sql/repmgr3.0_repmgr3.1.sql. This introduces one new convenience view, repl_show_nodes.
- Run the provided repmgr database upgrade script, repmgr3.1.1_repmgr3.1.2.sql. This makes a small modification to the repl_nodes table's foreign key definition.
- Restart repmgrd if previously stopped.
Community and development
repmgr is free and open source software and is licensed under the GPLv3.
Contributions to repmgr are welcome. See CONTRIBUTING.md for information about how to contribute.