Sample3_CreatingAVirtualNetwork.md

Example: Creating a Virtual Network

In this example, we'll create a virtual network. Since the SDK follows the resource hierarchy in Azure, we'll need to do this inside of a resource group.

Import the namespaces

These are the namespaces needed for this project:

using System;
using System.Threading.Tasks;
using Azure.Core;
using Azure.Identity;
using Azure.ResourceManager;
using Azure.ResourceManager.Resources;
using Azure.ResourceManager.Network;

Create a Resource Group

Start by creating a new resource group, like we did above:

ArmClient client = new ArmClient(new DefaultAzureCredential());
SubscriptionResource subscription = await client.GetDefaultSubscriptionAsync();
ResourceGroupCollection resourceGroups = subscription.GetResourceGroups();

string resourceGroupName = "myResourceGroup";
ResourceGroupData resourceGroupData = new ResourceGroupData(AzureLocation.WestUS2);
ArmOperation<ResourceGroupResource> operation = await resourceGroups.CreateOrUpdateAsync(WaitUntil.Completed, resourceGroupName, resourceGroupData);
ResourceGroupResource resourceGroup = operation.Value;

Create a Virtual Network

Now that we have a resource group, we'll create our virtual network. To do this, we will create a VirtualNetworkData object for the parameters that we want our Virtual Network to have, then we will get the Virtual Network collection and from there we call CreateOrUpdateAsync().

string vnetName = "myVnetName";
VirtualNetworkData vnetData = new VirtualNetworkData()
{
    // You can specify many options for the Virtual Network in here
    Location = "WestUS2",
    AddressSpace = new AddressSpace()
    {
        AddressPrefixes = { "10.0.0.0/16", }
    }
};

VirtualNetwork vnet = await resourceGroup.GetVirtualNetworks().CreateOrUpdateAsync(vnetName, vnetData);

Create a Subnet

Now that we have a virtual network, we must create at least one subnet in order to add any virtual machines. Following the hierarchy in Azure, subnets belong to a virtual network, so that's where we'll get our SubnetCollection instance. Before that, a SubnetData object must be created to specify the parameters for the Subnet.

string subnetName = vnetName + "_Subnet1";
SubnetData subnetData = new SubnetData()
{
    Name = subnetName,
    AddressPrefix = "10.0.1.0/24"
};

Subnet subnet = await vnet.GetSubnets().CreateOrUpdateAsync(subnetName, subnetData);

Another way to create a Virtual Network with a Subnet

It is possible to define an create a virtual network with its subnets in a single step. This is achieved by defining the subnets in the VirtualNetworkData object that is given as a parameter.

string vnetName = "myVnetName";
string subnet1Name = vnetName + "_Subnet1";

var vnetData = new VirtualNetworkData()
{
    Location = "WestUS2",
    AddressSpace = new AddressSpace()
    {
        AddressPrefixes = { "10.0.0.0/16", }
    },
    Subnets = { new SubnetData() { Name = subnet1Name, AddressPrefix = "10.0.0.0/24", } }
};

VirtualNetwork vnet = await resourceGroup.GetVirtualNetworks().CreateOrUpdateAsync(vnetName, vnetData);

Modifying the Subnets of an existing Virtual Network

Using the SubnetCollection it is possible to add a subnet into the virtual network we created above.

string subnet2Name = vnetName + "_Subnet2";
SubnetData subnetData = new SubnetData()
{
    Name = subnet2Name,
    AddressPrefix = "10.0.1.0/24"
};

Subnet subnet = await vnet.GetSubnets().CreateOrUpdateAsync(subnet2Name, subnetData);

You can verify that your virtual network now has 2 subnets by doing the following:

VirtualNetwork myVNet = await resourceGroup.GetVirtualNetworks().GetAsync(vnetName);
Console.WriteLine(myVNet.Data.Subnets.Count);