How to switch PHP version for CLI?

Run the below command and select the PHP version you want to switch to. In the below example, I’m switching the PHP version to 7.4.

Command Line: update-alternatives –config php

There are 4 choices for the alternative php (providing /usr/bin/php).

Selection  Path                     Priority      Status

• 0          /usr/bin/php8.0          80            auto mode
  1          /usr/bin/php5.6          56            manual mode
  2          /usr/bin/php7.0          70            manual mode
  3          /usr/bin/php7.4          74            manual mode
  4          /usr/bin/php8.0          80            manual mode

Press to keep the current choice[*], or type selection number: 3
update-alternatives: using /usr/bin/php7.4 to provide /usr/bin/php (php) in manual mode.

Note : But there is a problem in this; it will only change on the command line (CLI), but it won’t change in the browser.

Run the below commands to disable and enable multi PHP versions.

Commands :

a2dismod php7.4
a2enmod php8.1
Then Restart Ubuntu: systemctl restart apache2