PostgreSQL Upgrade from version 12 To 16 | Upgrading Postgres | step-by-step | CloudRevol Hosting

This article explains how to update PostgreSQL from Version 12 to Version 16 step-by-step. We'll also go over some best practices both before and after the PostgreSQL upgrade in this video.

Prerequisites

One Server with PostgreSQL 12 installed
Ubuntu 20.04 LTS
Shell access with sudo privileges

Note: Backed up current databases for precaution if process breaks or fail

Before starting, ensure you have access to your Ubuntu 20.04 LTS server with shell access and sudo privileges. Additionally, back up your current databases to safeguard against any issues during the upgrade process.

Step 1: Prepare for PostgreSQL 16 Installation

Access the Terminal

Log in to your Ubuntu 20.04 LTS server via SSH or directly if it's a local machine.

Add PostgreSQL Repository Key

Use wget to retrieve the PostgreSQL repository key:


Add PostgreSQL Repository

Add the PostgreSQL repository to your system's sources list:

Update System Packages

Update the package list to ensure you have access to the latest PostgreSQL version:

sudo apt update

Install PostgreSQL 16

Install PostgreSQL 16 along with the client:

sudo apt install postgresql-16 postgresql-client-16 -y

Verify Installation

Check if PostgreSQL 16 is installed correctly:

dpkg -l | grep postgresql

Check PostgreSQL Clusters

View the PostgreSQL clusters available:

pg_lsclusters

Step 2: Upgrade PostgreSQL

Stop PostgreSQL Service

Stop the PostgreSQL service to prepare for the upgrade:

sudo service postgresql stop

Drop Old PostgreSQL Cluster

Remove the old PostgreSQL 16 cluster:

sudo pg_dropcluster 16 main --stop

Upgrade PostgreSQL Cluster

Perform the upgrade of the main cluster from version 12 to 16:

sudo pg_upgradecluster 12 main

Step 3: Start PostgreSQL Service

Start PostgreSQL

Restart the PostgreSQL service:

sudo service postgresql start

Check PostgreSQL Clusters

Verify that PostgreSQL 16 is now active:

pg_lsclusters

Step 4: Drop Old PostgreSQL Cluster (Optional)

If you are certain that the upgrade was successful and you no longer need the old PostgreSQL 12 cluster:

Drop Old Cluster

Permanently remove the PostgreSQL 12 cluster:

sudo pg_dropcluster 12 main

Remember, upgrading a critical service like a database management system carries risks. Always ensure you have backups and test the process in a controlled environment before performing upgrades on a production system.

#postgresql #cloudrevol #tutorial #devops #upgrade #postgres

[ujjwalpl]

Very useful. Would have been great if fonts are slightly bigger

[gregbalson]

Thanks for the instructions, easy. But you do have a typo in the written comments, you indicate to drop the OLD data just before doing the upgrade, which doesn't work. You have "sudo pg_dropcluster 12 main --stop" but I think you want to drop the 16 cluster, not 12...then do the cluster upgrade. :)

[CloudRevolVerse]

It was very helpful to upgrade my 14 to 16 PostgreSQL

[iamsyedahiba]

Great to have, can you also share something on MS SQL Server ?

[HostingAgency-egxj]

multiple version of PostgreSQL is good to have.

[BaluShiva-ymhj]

I cant see pg_lsclusters command in my postgresql-13, could you help me?, i want to upgrade from 13 to 16 on centos 7