Installing pg_auto_failover

We provide native system packages for pg_auto_failover on most popular Linux distributions.

Use the steps below to install pg_auto_failover on PostgreSQL 11. At the current time pg_auto_failover is compatible with both PostgreSQL 10 and PostgreSQL 11.

Ubuntu or Debian

Postgres apt repository

Binary packages for debian and derivatives (ubuntu) are available from apt.postgresql.org repository, install by following the linked documentation and then:

$ sudo apt-get install pg-auto-failover-cli
$ sudo apt-get install postgresql-14-auto-failover

The Postgres extension named “pgautofailover” is only necessary on the monitor node. To install that extension, you can install the postgresql-14-auto-failover package when using Postgres 14. It’s available for other Postgres versions too.

Avoiding the default Postgres service

When installing the debian Postgres package, the installation script will initialize a Postgres data directory automatically, and register it to the systemd services. When using pg_auto_failover, it is best to avoid that step.

To avoid automated creation of a Postgres data directory when installing the debian package, follow those steps:

$ curl https://www.postgresql.org/media/keys/ACCC4CF8.asc | apt-key add -
$ echo "deb http://apt.postgresql.org/pub/repos/apt buster-pgdg main" > /etc/apt/sources.list.d/pgdg.list

# bypass initdb of a "main" cluster
$ echo 'create_main_cluster = false' | sudo tee -a /etc/postgresql-common/createcluster.conf
$ apt-get update
$ apt-get install -y --no-install-recommends postgresql-14

That way when it’s time to pg_autoctl create monitor or pg_autoctl create postgres there is no confusion about how to handle the default Postgres service created by debian: it has not been created at all.

Fedora, CentOS, or Red Hat

Quick install

The following installation method downloads a bash script that automates several steps. The full script is available for review at our package cloud installation instructions page url.

# add the required packages to your system
curl https://install.citusdata.com/community/rpm.sh | sudo bash

# install pg_auto_failover
sudo yum install -y pg-auto-failover14_12

# confirm installation
/usr/pgsql-12/bin/pg_autoctl --version

Manual installation

If you’d prefer to install your repo on your system manually, follow the instructions from package cloud manual installation page. This page will guide you with the specific details to achieve the 3 steps:

  1. install the pygpgme yum-utils packages for your distribution

  2. install a new RPM reposiroty for CitusData packages

  3. update your local yum cache

Then when that’s done, you can proceed with installing pg_auto_failover itself as in the previous case:

# install pg_auto_failover
sudo yum install -y pg-auto-failover14_12

# confirm installation
/usr/pgsql-12/bin/pg_autoctl --version

Installing a pgautofailover Systemd unit

The command pg_autoctl show systemd outputs a systemd unit file that you can use to setup a boot-time registered service for pg_auto_failover on your machine.

Here’s a sample output from the command:

$ export PGDATA=/var/lib/postgresql/monitor
$ pg_autoctl show systemd
13:44:34 INFO  HINT: to complete a systemd integration, run the following commands:
13:44:34 INFO  pg_autoctl -q show systemd --pgdata "/var/lib/postgresql/monitor" | sudo tee /etc/systemd/system/pgautofailover.service
13:44:34 INFO  sudo systemctl daemon-reload
13:44:34 INFO  sudo systemctl start pgautofailover
[Unit]
Description = pg_auto_failover

[Service]
WorkingDirectory = /var/lib/postgresql
Environment = 'PGDATA=/var/lib/postgresql/monitor'
User = postgres
ExecStart = /usr/lib/postgresql/10/bin/pg_autoctl run
Restart = always
StartLimitBurst = 0

[Install]
WantedBy = multi-user.target

Copy/pasting the commands given in the hint output from the command will enable the pgautofailer service on your system, when using systemd.

It is important that PostgreSQL is started by pg_autoctl rather than by systemd itself, as it might be that a failover has been done during a reboot, for instance, and that once the reboot complete we want the local Postgres to re-join as a secondary node where it used to be a primary node.