Ubuntu - Swap between PHP 5.5, 5.6 and 7.0

Hello,

This is tutorial how we can do it:

1. Install PHP 5.5:
• sudo apt-get install -y php5
2. Install PHP 5.6:
• sudo add-apt-repository ppa:ondrej/php
• In some case, you will need to change Ubuntu codename in this file:
• sudo vim /etc/apt/sources.list.d/ondrej-ubuntu-php-xenial.list
•  sudo apt-get update
• sudo apt-get install -y php5.6
3. Install PHP 7.0:
• sudo apt-get install -y php7.0
4.   Create symlink in your .bashrc file for quick access:
• vim ~/.bashrc
• Apache2:

• #################################################
  ############### PHP Version Toggle ##############
  #################################################
  # Remove the -q to see debugging information if there are problems
  alias enphp5.5="
   sudo a2dismod php5.6 -q;
   sudo a2dismod php7.0 -q;
   sudo a2enmod php5 -q;
   sudo ln -sf /usr/bin/php5 /usr/bin/php;
   sudo service apache2 restart"
  alias enphp5.6="
   sudo a2dismod php5 -q;
   sudo a2dismod php7.0 -q;
   sudo a2enmod php5.6 -q;
   sudo ln -sf /usr/bin/php5.6 /usr/bin/php;
   sudo service apache2 restart"
  alias enphp7.0="
   sudo a2dismod php5 -q;
   sudo a2dismod php5.6 -q;
   sudo a2enmod php7.0 -q;
   sudo ln -sf /usr/bin/php7.0 /usr/bin/php;
   sudo service apache2 restart"
  

• Nginx:
• Remove apache2:
• sudo service apache2 stop
• sudo apt-get remove apache2*
• sudo apt-get purge apache2
• Install php-fpm for all versions
• sudo apt-get install php5-fpm
• sudo apt-get install php5.6-fpm
• sudo apt-get install php7.0-fpm
• Stop all php-fpm:
• sudo service php5-fpm stop
• sudo service php5.6-fpm stop
• sudo service php7.0-fpm stop

• #################################################
  ############### PHP Version Toggle ##############
  #################################################
  # Remove the -q to see debugging information if there are problems
  alias enphp5.5="
   sudo ln -sf /usr/bin/php5 /usr/bin/php;
   sudo service php5.6-fpm stop;
   sudo service php7.0-fpm stop;
   sudo service php5-fpm start;
   sudo find /etc/nginx/sites-available -type f -exec sed -i 's,/run/php/php5.6-fpm.sock,/var/run/php5-fpm.sock,g;s,/run/php/php7.0-fpm.sock,/var/run/php5-fpm.sock,g' {} \;
   sudo service nginx restart"
  alias enphp5.6="
   sudo ln -sf /usr/bin/php5.6 /usr/bin/php;
   sudo service php5-fpm stop;
   sudo service php7.0-fpm stop;
   sudo service php5.6-fpm start;
   sudo find /etc/nginx/sites-available -type f -exec sed -i 's,/var/run/php5-fpm.sock,/run/php/php5.6-fpm.sock,g;s,/run/php/php7.0-fpm.sock,/run/php/php5.6-fpm.sock,g' {} \;
   sudo service nginx restart"
  alias enphp7.0="
   sudo ln -sf /usr/bin/php7.0 /usr/bin/php;
   sudo service php5-fpm stop;
   sudo service php5.6-fpm stop;
   sudo service php7.0-fpm start;
   sudo find /etc/nginx/sites-available -type f -exec sed -i 's,/var/run/php5-fpm.sock,/run/php/php7.0-fpm.sock,g;s,/run/php/php5.6-fpm.sock,/run/php/php7.0-fpm.sock,' {} \;
   sudo service nginx restart"
  

5. Reload your new .bashrc commands:
• source ~/.bashrc
6. Done, now you can try it with:
• enphp5.5
• php -v
• enphp5.6
• php -v
• enphp7.0
• php -v

Good luck!

Source: https://github.com/JREAM/phalcon-xenial