# Enhance Terminology Guide
# Master organisation
The Master organisation is the entity which installed Enhance and which owns and manages the servers. This organisation has access to the entire reseller hierarchy.
Sometimes referred to as a customer. An organisation is an entity which owns website and can be subscribes to packages. Multiple users (logins) can be members of an organisations.
A user is a login. A login can belong to multiple organisations and can switch between each organisation without leaving the control panel.
A Reseller is a customer which is subscribed to a plan with the Customers resource > 0. A reseller can create their own customers over which they have access and control. They can create Packages and subscribe their customers to those packages. Optionally a reseller can be granted the permission to create sub-resellers which share their package resources.
A cluster is a collection of servers forming a deployment of Enhance. A cluster can consist of 1 or more virtualised or bare metal servers.
Sometimes referred to as services. A role is a collection of microservices dedicated to providing a specific service within an Enhance cluster. Enhance Roles are Application, Backup, DNS, Database and Email. A server can have 1 or multiple roles installed on it depending on its intended function. For example, we recommend having a server within your Enhance cluster that is dedicated to providing backups. Websites will be placed on these roles according to the website placement settings under settings -> platform. An instance of a role can also be dedicated to a customer subscription to create managed VPS/dedicated hosting.
# php Containerisation
Each website's PHP processes as well as their user level SSH and cron jobs run within an isolated name space and are subject to hard system resource limits if configured on the hosting package. They cannot access the files of other websites even within the same subscription, nor can they start listening daemons on the public network interfaces of the host o/s.
# Control panel server (also known as primary server)
This is the server with control pane role installed (Enhance) This server provides the orchestration layer for the entire cluster as well as the publicly accessible API, frontend UI, phpMyAdmin and Roundcube websites. It will always have the Application and Database role installed. Customer websites can be placed on this server in addition to the control panel role however if you are running a large cluster we recommend disabling placement on the control panel server. On a multi server cluster we recommend running Apache on the Application role.
The control panel role cannot be uninstalled or moved to another server in your cluster.