Hello, Can I install 3 version of PHP 5 on my ispconfig 3.1.2: PHP 5.3, PHP 5.4 and PHP 5.6 my OS is Ubuntu 16.04 now I have php 7.0 and 5.6 for now I want to install PHP 5.3 and 5.4, can I use this tutorial for instalation PHP 5.3 and 5.4: https://www.howtoforge.com/tutorial/how-to-install-php-5-6-on-ubuntu-16-04/ Thank you very much!
yes, you can install multiple php versions, just follow the alternate php howto for each version you want to install.
