一段輝煌的回憶，一個冬日的故事

1. 為了讓php版本可以自由切換，首先關閉 proxy_fcgi

sudo a2dismod proxy_fcgi proxy; sudo service apache2 restart

2. 重新安裝PHP 5.6

事實上不用移除PHP7.0，我們可以將PHP 5.6安裝在一起

sudo add-apt-repository ppa:ondrej/php
sudo apt-get update
sudo apt-get install php7.0 php5.6 php5.6-mysql php-gettext php5.6-mbstring php-mbstring php7.0-mbstring php-xdebug libapache2-mod-php5.6 libapache2-mod-php7.0

3. 切換PHP版本

php5.6 to php7.0:

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

php7.0 to php5.6:

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

4.系統環境的php -v 也要一起調整

Switch From PHP 7.2 => PHP 5.6

Apache:-

sudo a2dismod php7.2
sudo a2enmod php5.6
sudo service apache2 restart

Command Line:-

sudo update-alternatives --set php /usr/bin/php5.6
sudo update-alternatives --set phar /usr/bin/phar5.6
sudo update-alternatives --set phar.phar /usr/bin/phar.phar5.6 
sudo update-alternatives --set phpize /usr/bin/phpize5.6
sudo update-alternatives --set php-config /usr/bin/php-config5.6

Switch From PHP 5.6 => PHP 7.2

Apache:-

sudo a2dismod php5.6
sudo a2enmod php7.2
sudo service apache2 restart

Command Line:-

sudo update-alternatives --set php /usr/bin/php7.2
sudo update-alternatives --set phar /usr/bin/phar7.2
sudo update-alternatives --set phar.phar /usr/bin/phar.phar7.2
sudo update-alternatives --set phpize /usr/bin/phpize7.2
sudo update-alternatives --set php-config /usr/bin/php-config7.2