Host Named site collections have now been the “recommended” approach, very much to the fact that SharePoint Online/Office 365 uses it and it is now the most tested (by Microsoft) method. 

Host-Named Site Collection (HNSC) is actually a means to have a separate DNS for each site collection rather than having all the site collections follow the URL of the web application (path-based site collections).

Microsoft recommends this by default and makes use of it in Office 365; as far as I know all site collections we create in Office 365 are Host-Named Site Collections (HSNC).

Step 1. Create a hosting web application.

Step 2.Create a Site Collection .

Step 3. DNS and Find New A Host ...

Step 4. Create Host Name Site Collection.

Step5. For Host Name Site Colection use only Powersehll .

 PowerShell command: –HostHeaderWebApplication 

To create a web application for host-named site collections

• The securityadmin fixed server role on the SQL Server instance.
• The db_owner fixed database role on all databases that are to be updated.

Example : 

########### Start Example #############

Add-pssnapin Microsoft.SharePoint.Powershell

# Parameters

$webAppHostHeader = 'http//portal.contoso.com'

$webAppName = 'Portal WebApp'

$siteTemplate = 'BLANKINTERNET#0'

$rootsiteTemplate = 'STS#0'
$AppPoolName= 'Host_Header_Name_Pool'

$AppPoolAccount='Contoso\sp_admin'

#DataBase Name

$DatabaseServer = 'sqltest' 

$DatabaseName  = 'WSS_HOST_Header_Site'

#Create Authentication Provider 

$sp= New-SPAuthenticationProvider -UseWindowsIntegratedAuthentication

#Create a New Web Application and Applicaton Pool

$AppPool=New-SPServiceApplicationPool -Name $AppPoolName -Account $AppPoolAccount

#Create a New Web Application and Applicaton Pool

New-SPWebApplication -Name $webAppName -HostHeader 'portal.contoso.com'  -port 80 -ApplicationPool $AppPoolName -ApplicationPoolAccount $AppPoolAccount -AuthenticationProvider $sp -DatabaseServer $DatabaseServer -DatabaseName $DatabaseName

#A root site collection is a requirement for any Web application. It is also necessary for crawling content.

#Create a rool site collection

New-SPSite 'http://portal.contoso.com' -Name 'Portal' -Description 'Portal on root' -OwnerAlias 'contoso\administrator' -language 1033 -Template 'STS#0'

# ***IIS Binding***--------must IIS Binding and iisreset then use next steps....

#Create a intranet site collection

New-SPSite 'http://intranet.contoso.com' -Name 'intranet' -Description 'intranet site' -OwnerAlias 'contoso\administrator' -HostHeaderWebApplication 'http://portal.contoso.com' -Template $siteTemplate

########### end Example #############

• New-SPWebApplication -Name 'Contoso Sites' -port 80 -ApplicationPool ContosoAppPool -ApplicationPoolAccount (Get-SPManagedAccount 'Contoso\JDoe') -AuthenticationProvider (New-SPAuthenticationProvider -UseWindowsIntegratedAuthentication) 

To create host-named site collections

New-SPSite 'http://portal.contoso.com' -HostHeaderWebApplication 'http://<servername>' -Name 'Portal' -Description 'Customer root' -OwnerAlias 'contoso\administrator' -language 1033 -Template 'STS#0'

Step 6. Managed Path for HNSC

New-SPManagedPath 'departments' –HostHeader

The following example shows a host-named site collection created at a managed path:
New-SPSite 'http://portal.contoso.com/departments/marketing' -HostHeaderWebApplication 'http://portal.contoso.com' -Name 'Marketing' -Description 'Portal Marketing' -OwnerAlias 'contoso\administrator' -language 1033 -Template 'STS#0'

Find out Path based and Host Based 

Determine host-named site collections in existing web applications 

$webApp = Get-SPWebapplication 'http://portal.contoso.com'

foreach($spSite in $webApp.Sites)

{

if ($spSite.HostHeaderIsSiteName) 

{ Write-Host $spSite.Url 'is host-named' }

else

{ Write-Host $spSite.Url 'is path based' }

}

 
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