Host Named Site Collection

A host-named site collection allows you to address a site collection with a unique DNS name, such as “http://collection1.com”. 

Typically you will create a SharePoint web application, and it contains many path-based site collections that share the same host name (DNS name).  For example, collection1 has a site collection at “http://mywebapp.com/sites/collection1”, and collection2 has a site collection at “http:// mywebapp.com/sites/collection2”.  These are referred to as path-based site collections, and is the recommendation for most corporate scenarios.  Host named site collections enable you to assign a unique DNS name to site collections.  For example, you can address them as http://collection1.com and http://collection2.com, which enables hosters to scale to many customers.

SharePoint makes the decision on how to map the host name to the site collection when the SPSite object is constructed.  It internally uses the SPWebApplication object to find the web application in the configuration database and determine if there is a host header associated with the site collection.  If no host header information is returned, this is a typical site collection.

Command

New-SPSite 'http://collection1.com' -HostHeaderWebApplication 'http://mywebapp' -Name 'Demo' -Description 'Demo' -OwnerAlias 'domain\administrator' -language 1033 -Template 'STS#0'

Advantages

1.      The ability to use managed paths with host-named site collections.

2.      The ability to use off-box SSL termination with host-named site collections. 

3.      Host-named site collections can also be used to implement multi tenancy solutions

Limitations

1.      Host Named site collection can be created using PowerShell only.

2.      In order to create host named site collection that has url same as web application, you must create site collection using SharePoint UI.

Regards,

Keyur Pandya