How can I downgrade from PHP 7 to PHP 5.6 on Ubuntu 16.04? / How to change php version in Ubuntu Apache

ubuntu-php-version-switch.md

Switch PHP version:

Note: change PHP version numbers to match your requirement. I have used 5.6 and 7.0

From php5.6 to php7.0 :

Apache:

Changing php version for Aapche server

sudo a2dismod php5.6 ; sudo a2enmod php7.0 ; sudo service apache2 restart

CLI:

Changing php version for command line usage

sudo ln -sfn /usr/bin/php7.0 /etc/alternatives/php

Issue

if it is not working still, you may need to disable the proxy_fcgi apache module and give it a try again

sudo a2dismod proxy_fcgi proxy; sudo service apache2 restart

From php7.0 to php5.6:

Apache:

Changing php version for Aapche server

sudo a2dismod php7.0 ; sudo a2enmod php5.6 ; sudo service apache2 restart

CLI:

Changing php version for command line usage

sudo ln -sfn /usr/bin/php5.6 /etc/alternatives/php

Issue

if it is not working still, you may need to disable the proxy_fcgi apache module and give it a try again

sudo a2dismod proxy_fcgi proxy; sudo service apache2 restart