Azure Virtual Network, virtual machines in Azure, internet access, etc. allows us to network securely to resources.

Before creating the Azure Virtual Network structure, I would like to explain the Address Space and Subnet issues.

Address Space: This is the part where we specify the ip range you want to use.

Subnet Allows us to divide the ip range we created in the Address Space section into multiple subnets. In this way we can create multiple network ranges from one Address Space block.

Address Space and Subnet as an example;

  • 192.168.0.0/16 (Address Space)

o 192.168.100.0/24 (Subnet)

o 192.168.110.0/24 (Subnet)

  • 10.0.0.0.0/16 (Address Space)

o 10.0.10.10.0/24 (Subnet)

o 10.0.20.0/25 (Subnet)

o 10.0.20.128/25 (Subnet)

All networks in this example will hear each other. If these networks are not running on Azure but on switches or etc. on one device, they wouldn’t hear each other.

Based on this example, I wanted to create an image of an Address Space and Subnet in your head before we get into the subject.

Let’s start the installation. First, we go to https://portal.azure.com.

Type Virtual Networks in the Search section.

Let’s start the steps to create our virtual network by clicking Create.

This installation consists of 5 tabs and I will talk about the basics.

  • Basics: Tab for categorization, naming and zoning.
  • IP Addresses: The tab where our network base is created.
  • Security: The tab with our security options.
  • Tags: The tab that allows us to do tagging.
  • Review+Create: The tab where we finish checking and creating.

Basics Tab

In the Project Details section, you can select Subscriptions in the Azure environment.

If a Resource group has not been created before, you can create and select a new Resource group with the “Create New” option.

Instance details section Name you must specify a unique name that is not found in Subscription. When creating it, make sure that it is easy to remember and distinguish it from the Virtual networks you want to create.

Region where we choose which region will be the Virtual Network we created in the Virtual Network section.

After completing these steps, we proceed to the next tab.

IP Addresses Tab

When creating Address Space, we specify a range as in the example I gave above. We will create a Subnet within this range.

I created sample address space and subnets. There is an important part to note here. As you know, Network ID and broadcast are out of use, in addition, the first 3 ip addresses in the same Subnet are used by Azure. In other words, a total of 5 ip addresses in the subnet are reserved by Azure.

Example of the first ip address;

  • 10.0.0.0.0/16 (Address Space)

o 10.0.10.10.0/24 (Subnet)> 10.0.10.10.4 (First ip address)

o 10.0.20.0/25 (Subnet)> 10.0.20.4 (First ip address)

o 10.0.20.128/25 (Subnet)> 10.0.20.132 (First ip address)

After completing these steps, we proceed to the next tab.

Security Tab

This section includes security and access services of our network blocks.

Bastion Host: A feature that we can perform RDP and SSH connections to Virtual Machines (VMs) more securely and smoothly without the need for public IP addresses. You can activate and integrate this feature into your system.

DDos Protection Standard: A feature provided by the Azure Vnet service that you do not manage yourself. You can provide basic DDoS security at no cost. You can activate and integrate this feature into your system.

Firewall: Cloud-based Network security service running in Azure environment. It is a security service that covers and protects Azure Virtual Network. You can activate and integrate this feature into your system.

After completing these steps, we proceed to the next tab.

Tags Tab

In this tab we create labeling. The part to be considered here is case sensitivity when entering Name and Value values. The value you enter in the “Name” section is not case sensitive. In the “Value” section, on the contrary, it is case sensitive. We can apply these tags to resource groups so that they can be categorized. It is shown in more detail when you click on “Learn more about tags” during installation.

After completing these steps, we proceed to the next tab.

Review + create Tab

This is the last step where we generally observe and check the configurations we have made. After performing the checks, click on “Create” and complete the installation.

If you have completed our installation without any problems, we will receive the “Validation passed” warning.

After completing your installation, “Validation failed. Required information is missing or not valid.” If you get the warning, you can go to the tab with “X” and check the configuration.

After the installation is finished, you can press “Go to Resource” or click on the menu at the top left in the Azure Portal interface. You can go to the Virtual Networks tab.

When we enter Vnet, we can see, add and modify general settings from here.

We have completed our Virtual Network creation steps. I hope it was helpful.

Author: Hasan Hüseyin Özer