Introduction

Creating a virtual network (VNet) with multiple subnets in Azure is essential for organizing and securing your cloud resources. This blog will walk you through creating a VNet with four subnets using the address space 192.148.30.0/26.

Step 1: Understanding the Address Space
The CIDR notation 192.148.30.0/26 means:

Network address: 192.148.30.0
Subnet mask: 255.255.255.192
Total number of IP addresses: 64 (2^6)
We need to divide this address space into four subnets. Each subnet will have a /28 prefix, giving us 16 IP addresses per subnet (2^4).

Step 2: Calculating the Subnets
Here's how we can divide the 192.148.30.0/26 address space into four /28 subnets:

Subnet 1: 192.148.30.0/28

Network address: 192.148.30.0
Broadcast address: 192.148.30.15
Usable IP range: 192.148.30.1 to 192.148.30.14

Subnet 2: 192.148.30.16/28

Network address: 192.148.30.16
Broadcast address: 192.148.30.31
Usable IP range: 192.148.30.17 to 192.148.30.30

Subnet 3: 192.148.30.32/28

Network address: 192.148.30.32
Broadcast address: 192.148.30.47
Usable IP range: 192.148.30.33 to 192.148.30.46

Subnet 4: 192.148.30.48/28

Network address: 192.148.30.48
Broadcast address: 192.148.30.63
Usable IP range: 192.148.30.49 to 192.148.30.62

Step-by-Step Guide to Creating an Azure Virtual Network with Four Subnets

Step 1. Create the Virtual Network:

Log in to the Azure Portal

Create a New Resource Group. Navigate to Resource group.

Click on Create.

Fill in the required details.

Resource group name: Give your resource group a name
Region: Select your preferred region.

Review and create.

Create.

Step 2. Create a Virtual Network:

Navigate to the Virtual network page
Click on virtual network

Click on create

Fill in the required details:
Name: Name of choice
Subscription: Select your subscription
Resource group: Previously created resource group
Region: Select the same region as your resource group
Click on next until IP addresses

Step 3. Configure IP address and Subnets:

Enter the IPV4 address for the virtual network which is 192.148.30.0/26, and from this network, there are going to be 64 addresses. Click on Add a Subnet.

Add Subnet.

Repeat the process till four subnets are created.

The subnet address range will be
Subnet-1 :192.148.30.0/28 - 192.148.30.15/28.
Subnet-2 :192.148.30.16/28 - 192.148.30.31/28.
Subnet-3 :192.148.30.32/28 - 192.148.30.47/28.
Subnet-4 :192.148.30.48/28 - 192.148.30.63/28.

Click on review + create

Click on Create.

When Your deployment is complete, click on Go to resource.

To have a view of the subnets created, click on Settings on the left pane and then on Subnets.

Conclusion:

In conclusion, creating an Azure Virtual Network with multiple subnets is a crucial step in organizing and securing your cloud resources. By following the steps outlined in this guide, you can efficiently set up a VNet with four subnets, each with its own address range. This setup not only enhances the management of your network resources but also provides a structured approach to network segmentation, improving both performance and security. With Azure's intuitive interface, the process is straightforward, allowing you to focus on optimizing your cloud infrastructure for your specific needs.