PLESK / shared hosting question

[techlists at phpcoderusa.com]

Hi,

I have a win10 laptop that has VirtualBox installed on it and on 
VirtualBox I have a LAMP "Shared Hosting" configuration.

This is on a private IP.  I use non-rountable domain names like 
"framework.internal".  I use the Win and Linux hosts files for DNS.  
Each of my "shared host" is configured with PHP-FPM, so each one has a 
unique user.

I am doing a new install of the Amazon S3 PHP SDK on my local net so I 
can redue my back up script.

On my PLESK box I have one install of the SDK and one script that is 
configured to backup all my hosts.

I just now realized PLESK is doing something that is not shared 
hosting...

On my local configuration it appears I have to install the SDK on each 
VHost and run one script for each VHost.

Do I understand?

How does PLESK get around this?

Thanks!!

Keith