This is very simple way to find php.ini file to make changes. You need to have access to these files, and SSH login.

Step 1: To quickly find the file type:

php -i | grep 'Configuration File'

It will show you the location of the file. For most VPS servers, the file is located is /usr/local/lib.

Step 2: Enter the following command to change the directory:

cd /usr/local/lib

Step 3: You can use ls command to confirm the location. This command will display list of all the files and directories in the current location.

ls

Step 4: To edit the file:

pico php.ini

That's all!