Merge pull request MicrosoftDocs#1970 from bjwhalen/patch-23

Update Disable-CsOnlineSipDomain.md

Author: kenwith

skype/skype-ps/skype/Disable-CsOnlineSipDomain.md

@@ -8,7 +8,8 @@ schema: 2.0.0
 # Disable-CsOnlineSipDomain
 
 ## SYNOPSIS
-
+**THIS IS PRELIMINARY DOCUMENTATION OF UPCOMING FUNCTIONALITY**
+These cmdlets are only for use by complex organizations having multiple on-premises deployments of Skype for Business Server or Lync Server. By using Disable-CsOnlineSipDomain as described below, organizations can safely synchronize users from multiple on-premises forests  containing Skype for Business Server into a single Office 365 tenant.  Note however, only 1 on-premise tenant can be in hybrid mode at a time.  Users in the non-hybrid forests would continue to be served by their on-premises deployment of Skype for Business Server (or Lync Server).
 ## SYNTAX
 
 ```
@@ -17,16 +18,19 @@ Disable-CsOnlineSipDomain -Domain <String> [-Tenant <System.Guid>] [-DomainContr
 ```
 
 ## DESCRIPTION
-{{Fill in the Description}}
+*This cmdlet is useful for organizations with multiple on-premises deployments of Skype for Business Server (or Lync Server).* If an organization intends to configure hybrid for 1 of those deployments, then this cmdlet must be run for all sip domains in any other on-premises deployment(s).
+
+This cmdlet may also be useful for organizations with on-premises deployments of Skype for Business Server that have not properly configured Azure AD Connect. If the organization does not sync msRTCSIP-DeploymentLocator for its users, then Skype for Business Online will attempt to provision users online, despite there being users on-premises.  While the correct fix is to update the configuration for Azure AD Connect to sync those attributes, using Disable-CsOnlineSipDomain, can also mitigate the problem until that configuration change can be made.  If this comdlet is run, any users that were previously provisioned online in that domain will be de-provisioned in Skype for Business Online.
+
 
 ## EXAMPLES
 
 ### Example 1
 ```powershell
-PS C:\> {{ Add example code here }}
+PS C:\> Disable-CsOnlineSipDomain -Domain  Fabrikam.com
 ```
 
-{{ Add example description here }}
+The cmdlet above disables the online sip domain Fabrikam.com.  This would be useful in the case where a company, Contoson.com, that  has Skype for Business acquires Fabkrikam, which also has an on-premises deployment of Skype for Business Server.  If Contoso is in hybrid mode with Skype for Business Online. or if the intent is to configure it for hybrid, then if the organization wants to synchroize identities from Fabrikam.com into the same O365 tenant, the organization must first run this cmdlet.
 
 ## PARAMETERS
 
@@ -133,5 +137,6 @@ For more information, see about_CommonParameters (http://go.microsoft.com/fwlink
 
 ### System.Object
 ## NOTES
+This cmdlets is for advanced scenarios only.  Organizations that are pure online or have only 1 on-premise deployment need not run this cmdlet.
 
 ## RELATED LINKS