Added DNS configuration article

Author: sharaths-cs

articles/vmware-cloudsimple/private-cloud-dns-forwarding.md

@@ -0,0 +1,52 @@
+--- 
+title: Azure VMware Solution - DNS forwarding from private cloud to on-premises
+description: Describes how to enable your CloudSimple Private Cloud DNS server to forward lookup of on-premises resources
+author: sharaths-cs
+ms.author: b-shsury 
+ms.date: 02/29/2020 
+ms.topic: article 
+ms.service: azure-vmware-cloudsimple 
+ms.reviewer: cynthn 
+manager: dikamath 
+---
+
+# Enable CloudSimple Private Cloud DNS servers to forward DNS lookup of on-premises resources to your DNS servers
+
+Private Cloud DNS servers can forward DNS lookup for any on-premises resources to your DNS servers.  Enabling the lookup allows Private Cloud vSphere components to look up any services running in your on-premises environment and communicate with them using fully qualified domain names (FQDN).
+
+## Scenarios 
+
+Forwarding DNS lookup for your on-premises DNS server allows you to use your Private Cloud for the following scenarios:
+
+1. Use Private Cloud as a disaster recovery setup for your on-premises VMware solution
+2. Use on-premises Active Directory as an identity source for your Private Cloud vSphere
+3. Use HCX for migrating virtual machines from on-premises to Private Cloud
+
+## Before you begin
+
+A network connection must be present from your Private Cloud network to your on-premises network for DNS forwarding to work.  You can set up network connection using:
+
+* [Connect from on-premises to CloudSimple using ExpressRoute](on-premises-connection.md)
+* [Set up a Site-to-Site VPN gateway](https://docs.microsoft.com/azure/vmware-cloudsimple/vpn-gateway#set-up-a-site-to-site-vpn-gateway)
+
+Firewall ports must be opened on this connection for DNS forwarding to work.  Ports used are TCP port 53 or UDP port 53.
+
+> [!NOTE]
+> If you are using Site-to-Site VPN, your on-premises DNS server subnet must be added as a part of on-premises prefixes.
+
+## Request DNS forwarding from Private Cloud to on-premises
+
+To enable DNS forwarding from Private Cloud to on-premises, submit a [support request](https://portal.azure.com/#blade/Microsoft_Azure_Support/HelpAndSupportBlade/newsupportrequest), providing the following information.
+
+* Issue type: **Technical**
+* Subscription: **Subscription where CloudSimple service is deployed**
+* Service: **VMware Solution by CloudSimple**
+* Problem type: **Advisory or How do I...**
+* Problem subtype: **Need help with NW**
+* Provide the domain name of your on-premises domain in the details pane.
+* Provide the list of your on-premises DNS servers to which the lookup will be forwarded from your private cloud in the details pane.
+
+## Next steps
+
+* [Learn more about on-premises firewall configuration](on-premises-firewall-configuration.md)
+* [On-premises DNS server configuration](on-premises-dns-setup.md)

articles/vmware-cloudsimple/toc.yml

@@ -136,6 +136,8 @@
         href: on-premises-dns-setup.md
       - name: Configure highly available Site-to-Site VPN connections
         href: high-availability-vpn-connection.md
+      - name: Private Cloud DNS configuration to on premises
+        href: private-cloud-dns-forwarding.md
     - name: VMware platform
       items:
       - name: Learn Private Cloud permission model