1.1 Design and Implement IP Addressing for Azure Resources
📘Microsoft Azure Networking Solutions (AZ-700)
1. What is an Azure Virtual Network (VNet)?
An Azure Virtual Network (VNet) is a private network inside Azure.
It allows Azure resources such as:
- Virtual machines (VMs)
- Azure services
- Containers
to communicate securely with each other.
A VNet works like a private IP network in a data center, but it is fully managed by Azure.
Key Points for Exam
- A VNet is isolated by default
- Only resources inside the VNet can communicate unless you allow access
- VNets use private IP addressing
2. Why Do We Create a VNet?
You create a VNet to:
- Control IP addressing
- Control network traffic
- Secure communication between Azure resources
- Connect Azure to on-premises networks or other VNets
AZ-700 Focus
The exam checks if you understand:
- How VNets are created
- How IP ranges are planned
- How subnetting works inside a VNet
3. Core Components of a VNet
When creating a VNet, you must understand these components:
3.1 Address Space
An address space defines the IP range for the VNet.
- Uses private IP ranges
- Written in CIDR format
Common Private IP Ranges
10.0.0.0/8172.16.0.0/12192.168.0.0/16
Exam Rules
- Address spaces must not overlap with other VNets or on-premises networks
- IP planning is critical before creating the VNet
3.2 Subnets
A subnet divides a VNet into smaller networks.
- Every VNet must have at least one subnet
- Subnets help organize resources
- Each subnet has its own IP range
Important Subnet Rules
- Subnet IP range must be inside the VNet address space
- Subnet ranges cannot overlap
- Subnets can be resized (with limits)
Exam Tip
Azure reserves 5 IP addresses in every subnet:
- First IP (network address)
- Last IP (broadcast)
- 3 additional Azure-reserved addresses
4. Steps to Create a Virtual Network (Conceptual)
The exam does not test button-clicking, but you must know the logical steps.
Step 1: Choose Subscription and Resource Group
- VNets must belong to a resource group
- Resource group controls management and access
Step 2: Define VNet Name and Region
- VNets are regional
- Resources communicate faster inside the same region
Step 3: Configure Address Space
- Define the main IP range for the VNet
- Use CIDR notation
Step 4: Create Subnets
- Create one or more subnets
- Assign smaller IP ranges from the VNet address space
5. VNet Region and Scope
Regional Scope
- A VNet exists in one Azure region
- Resources in different regions need:
- VNet peering
- VPN
- ExpressRoute
Exam Reminder
VNets cannot span regions, but can connect across regions.
6. Default Settings During VNet Creation
When creating a VNet, Azure allows you to configure:
6.1 DNS Settings
- Azure provides default DNS
- You can specify custom DNS servers
Exam Focus
Custom DNS is often used when:
- Integrating with on-premises environments
- Using private name resolution
6.2 Security Defaults
VNets are:
- Private by default
- No inbound internet access unless configured
Security is enforced using:
- Network Security Groups (NSGs)
- Azure Firewall (advanced scenarios)
7. Important Design Considerations (Very Important for Exam)
7.1 IP Address Planning
- Plan for future growth
- Avoid overlapping IP ranges
- Consider hybrid connectivity
7.2 Subnet Size Planning
- Small subnets can cause IP exhaustion
- Azure reserves IPs automatically
7.3 Service Requirements
Some Azure services require:
- Dedicated subnets
- Specific subnet names
- Minimum subnet sizes
This is commonly tested in scenario-based questions.
8. VNet and Azure Services Integration
A VNet can integrate with:
- Virtual machines
- Load balancers
- Application gateways
- Private endpoints
- VPN gateways
Exam Tip
Not all Azure services need a VNet, but many advanced networking services do.
9. VNet Limits (High-Level Awareness)
For the exam, remember:
- VNets have limits (subnets, IPs, peerings)
- Limits depend on:
- Subscription
- Azure region
- Limits can often be increased by request
You are not expected to memorize numbers, but you should know limits exist.
10. Common Exam Mistakes to Avoid
❌ Overlapping address spaces
❌ Forgetting subnet IP reservations
❌ Assuming VNets span regions
❌ Thinking VNets allow internet access by default
11. How This Topic Appears in the AZ-700 Exam
You may see:
- Scenario-based questions
- IP range selection questions
- Subnet planning questions
- Hybrid network design questions
Example Exam Focus Areas
- Choose correct address space
- Identify correct subnet design
- Understand when VNets can or cannot communicate
12. Key Takeaways (Must Remember)
✔ A VNet is a private network in Azure
✔ VNets require IP address planning
✔ Subnets divide VNets into smaller networks
✔ VNets are region-specific
✔ Proper design prevents future network issues
