Install and use different versions of PHP

Dec 18, 2022 by Thibault Debatty | 257 views

PHP Sysadmin

https://cylab.be/blog/249/install-and-use-different-versions-of-php

When working on different projects, you may have to switch between different versions of PHP. In this blog post we show how to install and use different versions PHP on Ubuntu.

Install different versions of PHP

To install different versions of PHP we will install the ondrej/php PPA repository:

sudo apt install software-properties-common
sudo add-apt-repository ppa:ondrej/php
sudo apt update

Now we can install the desired version(s) of PHP. For example:

sudo apt install php7.4-cli php8.1-cli

At the time of writing, you can choose from

  • php5.6
  • php7.0
  • php7.1
  • php7.2
  • php7.3
  • php7.4
  • php8.0
  • php8.1
  • php8.2

You can also check available versions by yourself with

sudo apt search php.*-cli

Switch between and use different versions of PHP

So now you should have different versions of PHP installed. To know which version is currently in use, you can simply type

php --version

To switch to another version, you can use update-alternatives. First you can list the installed versions with

sudo update-alternatives --list php

php-versions-list.png

Now you can change to another version with update-alternatives --set. For example:

sudo update-alternatives --set php /usr/bin/php8.1

php-versions-set.png

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