text: Episerver CMS is multi-tenant, which.
  You have the following options to add new websites:
  Note: Even though CMS is multi-tenant, you you run CMS in multiple processes, you have to configure the event system for inter-process events. As a best practice, always consider using load-balancing for fault tolerance instead of separating sites into IIS sites.
  The following steps show how you set up multiple sites:
  If you configure the IIS application to respond to any host name, then you can launch new sites from the CMS admin view without needing any additional configuration. To define multiple sites, select Config tab > Manage Websites. You can add new sites and update existing sites. The website URL acts as a default URL to the website in cases where links are generated to the website.
  You need only a start page and a URL for the new site. The URL and start page are stored in the database, and new sites are automatically provisioned. When you launch new sites, you can also configure them to use site-specific assets. For example, when you create a campaign website, editors may want to store assets in folders only available to that specific campaign site.
  By default, one of the installed sites has the * (wild card) host mapping. You can also add additional hosts mappings, such as partner.examplesite.com or customer.examplesite.com, optionally bound to a specific language. You can also set up additional hosts that only should redirect to the main host or a specific host that should serve as the primary host for a specific language and the target for all redirects. Redirects only apply to content; to redirect a complete site, use settings in IIS instead.
  Implementation code running under a web request, such as templates, does not need to take into account that multiple websites exist, because CMS automatically routes requests to the correct site. You can access the current site using the SiteDefinition.Current property (in the namespace EPiServer.Web)..
  A possible misconception regarding authentication in multi-site setup is that logging out of one site while being logged in on other sites would also log you out from these websites. This is not the case because when you use Forms Authentication, by default, it stores authentication in a cookie per domain in the visitor's browser.
  Last updated: Oct 26, 2016