AddNode.ps1 execution parameters modified

We have multiple customers running into the below error while executing the AddNode.ps1 script (without certificate credentials) : 

Error message: 
Runtime package cannot be downloaded. Check your internet connectivity. If the cluster is not connected to the internet run Get-Servic
eFabricClusterUpgrade and note the TargetCodeVersion. Run Get-ServiceFabricRuntimeSupportedVersion from a machine connected to the internet to get the download links for all supported fabric versions. Download the package corresponding to your TargetCodeVersion. Pass -FabricRuntimePackageOutputDirectory <Path to runtime package> to AddNode.ps1 in addition to other parameters. Exception thrown : System.Fabric.FabricTransientException: Could not ping any of the provided Service Fabric gateway endpoints. ---> System.Runtime.InteropServices.COMException: Exception from HRESULT: 0x80071C49
 
With the suggested changes, the script runs successfully.

Author: Meghna-Chauhan

articles/service-fabric/service-fabric-cluster-windows-server-add-remove-nodes.md

@@ -22,15 +22,19 @@ After you have [created your standalone Service Fabric cluster on Windows Server
 
 ## Add nodes to your cluster
 
-1. Prepare the VM/machine you want to add to your cluster by following the steps outlined in [Plan and prepare your Service Fabric cluster deployment](service-fabric-cluster-creation-for-windows-server.md)
+1. Prepare the VM/machine you want to add to your cluster by following the steps outlined in [Plan and prepare your Service Fabric cluster deployment](service-fabric-cluster-creation-for-windows-server.md) 
+(For an exiting cluster, you do not need to follow the steps to create the cluster, ensure that the Service fabric Standalone package and Service fabric Runtime cab file is present on the new node)
 2. Identify which fault domain and upgrade domain you are going to add this VM/machine to
 3. Remote desktop (RDP) into the VM/machine that you want to add to the cluster
 4. Copy or [download the standalone package for Service Fabric for Windows Server](https://go.microsoft.com/fwlink/?LinkId=730690) to the VM/machine and unzip the package
 5. Run Powershell with elevated privileges, and navigate to the location of the unzipped package
-6. Run the *AddNode.ps1* script with the parameters describing the new node to add. The example below adds a new node called VM5, with type NodeType0 and IP address 182.17.34.52, into UD1 and fd:/dc1/r0. The *ExistingClusterConnectionEndPoint* is a connection endpoint for a node already in the existing cluster, which can be the IP address of *any* node in the cluster.
-
+6. Run the *AddNode.ps1* script with the parameters describing the new node to add. The example below adds a new node called VM5, with type NodeType0 and IP address 182.17.34.52, into UD1 and fd:/dc1/r0. The *ExistingClusterConnectionEndPoint* is a connection endpoint for a node already in the existing cluster, which can be the IP address of *any* node in the cluster. The cluster certificate used below should be installed under Personal (My) store of the current user. 
 	```
-	.\AddNode.ps1 -NodeName VM5 -NodeType NodeType0 -NodeIPAddressorFQDN 182.17.34.52 -ExistingClientConnectionEndpoint 182.17.34.50:19000 -UpgradeDomain UD1 -FaultDomain fd:/dc1/r0 -AcceptEULA
+	
+	$CertThumbprint= "***********************"
+
+.\AddNode.ps1 -NodeName VM5 -NodeType NodeType0 -NodeIPAddressorFQDN 182.17.34.52 -ExistingClientConnectionEndpoint 182.17.34.50:19000 -UpgradeDomain UD1 -FaultDomain fd:/dc1/r0 -X509Credential -ServerCertThumbprint $CertThumbprint  -AcceptEULA
+
 	```
 	Once the script finishes running, you can check if the new node has been added by running the [Get-ServiceFabricNode](/powershell/module/servicefabric/get-servicefabricnode?view=azureservicefabricps) cmdlet.