1.1 Design and Implement IP Addressing for Azure Resources
📘Microsoft Azure Networking Solutions (AZ-700)
1. What is a Public IP Address in Azure?
A Public IP address in Azure is an IP address that is reachable from the internet.
- It allows external users or systems to connect to your Azure resources like Virtual Machines (VMs), Load Balancers, and Azure Application Gateways.
- Without a public IP, your Azure resources are only accessible inside your virtual network (private IP only).
Key Point for Exam:
- Every public-facing service in Azure usually needs a public IP.
- Azure supports both IPv4 and IPv6 addresses for public access.
2. Types of Public IP Addresses
Azure offers two main types of public IP addresses:
a) Static Public IP
- Definition: The IP address does not change once it’s assigned.
- Use Case: Good for services that need a fixed address for DNS, firewalls, or external partners.
- IT Example: You host a corporate web server in Azure, and clients access it via a fixed IP or DNS name.
b) Dynamic Public IP
- Definition: The IP address can change when the resource is restarted or deallocated.
- Use Case: Suitable for temporary or less critical services where the IP doesn’t need to stay the same.
- IT Example: A test VM used for temporary development work.
Key Exam Point:
- Dynamic IPs are cheaper but not recommended for production that needs consistent access.
- Static IPs are required for DNS or firewall rules that rely on a fixed IP.
3. SKU Types of Public IP Addresses
Azure has two SKUs (Stock Keeping Units) for public IP addresses:
a) Basic SKU
- Lower-cost option.
- Only supports one-to-one IP to resource mapping.
- Works with classic and some standard workloads.
- Limited zone resiliency (cannot guarantee availability across multiple regions).
b) Standard SKU
- Higher availability and performance.
- Supports zone redundancy, meaning the IP is resilient across availability zones.
- Needed for resources behind Azure Load Balancer Standard or Azure Firewall.
Exam Tip:
- If you’re using Azure Standard Load Balancer, always use a Standard SKU public IP.
4. IP Address Assignment Options
When creating a public IP, you need to choose:
- Assignment: Static vs Dynamic
- SKU: Basic vs Standard
- IP Version: IPv4 or IPv6
- DNS Name Label (optional) – This allows users to access your resource with a friendly domain name like
myapp.eastus.cloudapp.azure.com.
IT Example:
- You deploy a web API and assign it a static, Standard, IPv4 public IP with a DNS label. Now, external apps can reliably call your API using that DNS name.
5. Creating a Public IP in Azure
You can create a public IP in three main ways:
a) Azure Portal
- Go to Azure Portal → Create a Resource → Networking → Public IP Address.
- Fill in:
- Name: Give a unique name.
- SKU: Basic or Standard.
- IP Version: IPv4 or IPv6.
- Assignment: Static or Dynamic.
- DNS Name Label (optional): For friendly DNS access.
- Click Review + Create → Create.
b) Azure CLI
# Example: Create a static, Standard IPv4 public IP
az network public-ip create \
--resource-group MyResourceGroup \
--name MyPublicIP \
--sku Standard \
--allocation-method Static \
--version IPv4
c) Azure PowerShell
# Example: Create a dynamic, Basic IPv4 public IP
New-AzPublicIpAddress -Name MyPublicIP -ResourceGroupName MyResourceGroup `
-AllocationMethod Dynamic -Sku Basic -IpAddressVersion IPv4
Exam Tip:
- Understand how to create both static and dynamic IPs in Portal, CLI, and PowerShell.
- Know the differences in SKU, assignment, and version, because exam questions often test scenarios.
6. Where Public IPs Are Used in IT
Here’s how Azure public IPs are commonly used in IT environments:
| Azure Resource | Role of Public IP |
|---|---|
| Virtual Machines (VMs) | Remote access via RDP/SSH from the internet. |
| Load Balancer | Distribute incoming traffic from the internet to backend VMs. |
| Azure Firewall | Acts as a single public-facing IP for outbound/inbound traffic. |
| Application Gateway | Provides HTTPS endpoint for web applications. |
| Azure Bastion | Secure remote management access to VMs without exposing them publicly. |
Key Exam Concept:
- Public IP is not mandatory for all resources.
- It’s only required when internet-facing access is needed.
- Azure recommends minimizing public exposure and using private IPs + VPN/ExpressRoute when possible.
7. Exam-Focused Summary
- Public IP → IP reachable from the internet.
- Static vs Dynamic → Static = fixed, Dynamic = changes over time.
- Basic vs Standard SKU → Standard for high availability and security, Basic for simple workloads.
- IPv4 vs IPv6 → Choose depending on client requirements.
- DNS Label → Optional friendly name for easier access.
- Used by → VM, Load Balancer, Firewall, App Gateway, Bastion.
- Creation → Portal, CLI, PowerShell.
Remember: Exam questions often give a scenario like:
“You need a public IP that never changes for a web app behind a Standard Load Balancer.”
Answer: Static, Standard SKU, IPv4 public IP.
