Merge pull request #234894 from pagienge/patch-7

Update tutorial-create-route-table-cli.md

Author: prmerger-automator[bot]

articles/virtual-network/tutorial-create-route-table-cli.md

@@ -25,7 +25,7 @@ Azure automatically routes traffic between all subnets within a virtual network,
 * Create a route
 * Create a virtual network with multiple subnets
 * Associate a route table to a subnet
-* Create an NVA that routes traffic
+* Create a basic NVA that routes traffic from an Ubuntu VM
 * Deploy virtual machines (VM) into different subnets
 * Route traffic from one subnet to another through an NVA
 
@@ -112,9 +112,9 @@ az network vnet subnet update \
 
 ## Create an NVA
 
-An NVA is a VM that performs a network function, such as routing, firewalling, or WAN optimization.
+An NVA is a VM that performs a network function, such as routing, firewalling, or WAN optimization.  We will create a basic NVA from a general purpose Ubuntu VM, for demonstration purposes. 
 
-Create an NVA in the *DMZ* subnet with [az vm create](/cli/azure/vm). When you create a VM, Azure creates and assigns a network interface *myVmNvaVMNic* and a public IP address to the VM, by default. The `--public-ip-address ""` parameter instructs Azure not to create and assign a public IP address to the VM, since the VM doesn't need to be connected to from the internet. If SSH keys do not already exist in a default key location, the command creates them. To use a specific set of keys, use the `--ssh-key-value` option.
+Create a VM to be used as the NVA in the *DMZ* subnet with [az vm create](/cli/azure/vm). When you create a VM, Azure creates and assigns a network interface *myVmNvaVMNic* and a public IP address to the VM, by default. The `--public-ip-address ""` parameter instructs Azure not to create and assign a public IP address to the VM, since the VM doesn't need to be connected to from the internet. If SSH keys do not already exist in a default key location, the command creates them. To use a specific set of keys, use the `--ssh-key-value` option.
 
 ```azurecli-interactive
 az vm create \
@@ -138,7 +138,7 @@ az network nic update \
   --ip-forwarding true
 ```
 
-Within the VM, the operating system, or an application running within the VM, must also be able to forward network traffic. Enable IP forwarding within the VM's operating system with [az vm extension set](/cli/azure/vm/extension):
+Within the VM, the operating system, or an application running within the VM, must also be able to forward network traffic.  We will use the `sysctl` command to enable the Linux kernel to forward packets.  To run this command without logging onto the VM, we will use the [Custom Script extension](/azure/virtual-machines/extensions/custom-script-linux) [az vm extension set](/cli/azure/vm/extension):
 
 ```azurecli-interactive
 az vm extension set \
@@ -149,7 +149,7 @@ az vm extension set \
   --settings '{"commandToExecute":"sudo sysctl -w net.ipv4.ip_forward=1"}'
 ```
 
-The command may take up to a minute to execute.
+The command may take up to a minute to execute.  Note that this change will not persist after a VM reboot, so if the NVA VM is rebooted for any reason, the script will need to be repeated.
 
 ## Create virtual machines
 
@@ -203,7 +203,7 @@ Take note of the **publicIpAddress**. This address is used to access the VM from
 
 ## Route traffic through an NVA
 
-Use the following command to create an SSH session with the *myVmPrivate* VM. Replace *\<publicIpAddress>* with the public IP address of your VM. In the example above, the IP address is *13.90.242.231*.
+Using an SSH client of your choice, connect to the VMs created above.  For example, the following command can be used from a command line interface such as [WSL](/windows/wsl/install) to create an SSH session with the *myVmPrivate* VM. Replace *\<publicIpAddress>* with the public IP address of your VM. In the example above, the IP address is *13.90.242.231*.
 
 ```bash
 ssh azureuser@<publicIpAddress>
@@ -214,13 +214,10 @@ When prompted for a password, enter the password you selected in [Create virtual
 Use the following command to install trace route on the *myVmPrivate* VM:
 
 ```bash
-sudo apt-get update
-sudo apt-get upgrade
-sudo apt-get install traceroute
+sudo apt update
+sudo apt install traceroute
 ```
 
-
-
 Use the following command to test routing for network traffic to the *myVmPublic* VM from the *myVmPrivate* VM.
 
 ```bash