1. 6) Check the Xdebug log - it will tell where it tries to connect to and what the response is. If log is empty: A) wrong path (Ubuntu virtualizes if /tmp/ is used); B) file permissions C) Xdebug is not trying to debug anything D) Something prevents that (e.g. SELinux or alike) - rather unlikely to happen in containers, but may still affect Apache.
2. You can see the flow of the PHP code, and there is a tool. It is called Xdebug. Here we can see how to configure the Xdebug with PhpStorm IDE. I nstall Xdebug on Ubuntu using following cmd.

1. Phpstorm Xdebug Ssh
2. Xdebug Phpstorm Ubuntu Windows 10
3. Xdebug Phpstorm Ubuntu Free

In this video I show you how to install Xdebug on Ubuntu and configure it to work with PhpStorm's Xdebug tools. NEVER type vardump again!For Magento 2 devel.

Why do we need Xdebug?

In the development process, we have several existing codes with a number of functionalities. We don’t have to create that functionality from the core every time. We can rather use the existing code and make simple modifications that will save our time and energy. Product development processes work the same. Before modifying the existing code, we need to know how they work and which codes have which functionality.

Now you may have the question, can we see how the PHP code works? It is a virtual object, right?

Absolutely! You can see the flow of the PHP code, and there is a tool. It is called Xdebug. Here we can see how to configure the Xdebug with PhpStorm IDE.

Install Xdebug on Ubuntu using following cmd:

Once you have installed the Xdebug into your system, restart your apache2 server and enable error tracing using the below cmd.