Public IPs

🎯 Lab Objectives

In this hands-on lab, you will learn how to:

• Understand the purpose and types of Azure Public IP addresses
• Manually provision Public IPs and Network Interfaces (NICs)
• Associate Public IPs with NICs and attach them to Virtual Machines
• Configure different SKUs and allocation methods for Public IPs
• Test connectivity to VMs using the assigned Public IPs
• Understand security implications of public IP assignment

Goal: Configure public IP connectivity for Windows and Linux VMs by creating and associating network components.

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🏗️ Pre-Provisioned Environment

The following Azure resources have been pre-deployed in your environment:

Resource Overview

Resource Type	Resource Name	Configuration	Purpose
Resource Group	PublicIP-Lab-RG	Contains all lab resources	Logical container
Virtual Network	PublicIPLab-VNet	Address space: 10.0.0.0/16	Network foundation
Subnet	LabSubnet	Range: 10.0.0.0/24	VM network segment
Windows VM	WinVM	Windows Server 2019	Target for RDP access
Linux VM	LinuxVM	Ubuntu 20.04 LTS	Target for SSH access

Network Architecture

PublicIPLab-VNet (10.0.0.0/16)
└── LabSubnet (10.0.0.0/24)
    ├── WinVM (No NIC/Public IP - to be configured)
    └── LinuxVM (No NIC/Public IP - to be configured)

VM Details

VM	Operating System	Default State	Access Method
WinVM	Windows Server 2019	No public connectivity	RDP (port 3389)
LinuxVM	Ubuntu 20.04 LTS	No public connectivity	SSH (port 22)

🔍 Note: VMs are deployed without NICs or Public IPs - you’ll create and attach these components during the lab.

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🚀 Lab Exercises

Part 1: Create Public IP Addresses

Step 1: Navigate to Public IP Creation

1. Open the Azure Portal
2. Navigate to PublicIP-Lab-RG resource group
3. Click + Create
4. Search for “Public IP address”
5. Select Public IP address by Microsoft
6. Click Create

Step 2: Create Windows VM Public IP

Configure the first Public IP:

Setting	Value	Notes
Subscription	Your subscription	Pre-selected
Resource group	PublicIP-Lab-RG	Use existing
Name	WinVM-PublicIP	Descriptive name
Region	Same as resource group	Must match VNet
IP Version	IPv4	Standard protocol
SKU	Standard	Recommended for production
Availability zone	Zone-redundant	High availability
Tier	Regional	Single region
IP address assignment	Static	Permanent IP

Step 3: Configure Additional Settings

Setting	Value	Purpose
Routing preference	Microsoft network	Optimal routing
Idle timeout	4 minutes	Default value
DNS name label	winvm-[your-initials]-[random]	Optional: Creates FQDN

1. Click Review + create
2. Click Create

Step 4: Create Linux VM Public IP

Repeat the process with these settings:

Setting	Value	Notes
Name	LinuxVM-PublicIP	Linux VM identifier
SKU	Standard	Same as Windows VM
IP address assignment	Static	Permanent assignment
DNS name label	linuxvm-[your-initials]-[random]	Optional FQDN

⏱️ Creation Time: Public IPs typically create within 1-2 minutes.

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Part 2: Create Network Interfaces (NICs)

Step 1: Navigate to NIC Creation

1. In PublicIP-Lab-RG, click + Create
2. Search for “Network interface”
3. Select Network interface by Microsoft
4. Click Create

Step 2: Create Windows VM Network Interface

Configure the first NIC:

Setting	Value	Notes
Subscription	Your subscription	Pre-selected
Resource group	PublicIP-Lab-RG	Use existing
Name	WinVM-NIC	Windows VM NIC
Region	Same as resource group	Must match VNet
Virtual network	PublicIPLab-VNet	Target network
Subnet	LabSubnet	VM subnet
Network security group	Advanced	Configure NSG
Configure network security group	Create new	New NSG for RDP

Step 3: Configure NSG for Windows

1. Click Create new for NSG
2. Name it: WinVM-NSG
3. Add inbound rule:

Setting	Value	Purpose
Source	My IP address	Your current IP
Source port ranges	*	Any source port
Destination	Any	Any destination
Service	RDP	Remote Desktop
Action	Allow	Permit RDP
Priority	1000	Rule precedence
Name	Allow-RDP	Descriptive name

4. Click OK to create NSG

Step 4: Associate Public IP

Setting	Value	Notes
Public IP address	Associate	Enable public IP
Public IP address	WinVM-PublicIP	Previously created IP
Private IP address assignment	Dynamic	DHCP assignment

5. Click Review + create
6. Click Create

Step 5: Create Linux VM Network Interface

Repeat the process with these settings:

Setting	Value	Notes
Name	LinuxVM-NIC	Linux VM NIC
Virtual network	PublicIPLab-VNet	Same network
Subnet	LabSubnet	Same subnet
Network security group	Create new: LinuxVM-NSG	SSH access
Public IP address	LinuxVM-PublicIP	Previously created

Step 6: Configure SSH Rule for Linux NSG

Add inbound rule for SSH:

Setting	Value	Purpose
Source	My IP address	Your current IP
Service	SSH	Secure Shell
Action	Allow	Permit SSH
Priority	1000	Rule precedence
Name	Allow-SSH	Descriptive name

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Part 3: Attach NICs to Virtual Machines

Step 1: Stop Virtual Machines

1. Navigate to WinVM
2. Click Stop in the toolbar
3. Wait for VM to fully stop (Status: Stopped (deallocated))
4. Repeat for LinuxVM

⚠️ Important: VMs must be fully stopped (deallocated) before attaching NICs.

Step 2: Attach NIC to Windows VM

1. Go to WinVM
2. In the left menu, click Networking
3. Click Attach network interface
4. Select WinVM-NIC
5. Click OK

Step 3: Set Primary Network Interface

1. In WinVM networking settings
2. Click WinVM-NIC
3. Click Set as primary
4. Confirm the action

Step 4: Attach NIC to Linux VM

1. Go to LinuxVM
2. In the left menu, click Networking
3. Click Attach network interface
4. Select LinuxVM-NIC
5. Click OK
6. Set LinuxVM-NIC as primary

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Part 4: Test Connectivity

Step 1: Start Virtual Machines

1. Navigate to WinVM
2. Click Start
3. Wait for VM to fully start
4. Repeat for LinuxVM

Step 2: Get Public IP Addresses

1. Click on WinVM-PublicIP
2. Copy the IP address from the overview page
3. Record: WinVM Public IP: _______________
4. Repeat for LinuxVM-PublicIP
5. Record: LinuxVM Public IP: _______________

Step 3: Test RDP to Windows VM

1. Open Remote Desktop Connection on your local machine
2. Enter the WinVM Public IP address
3. Click Connect
4. Use these credentials:
   • Username: azureuser
   • Password: LabPassword123!
5. Expected Result: ✅ Successful RDP connection

Step 4: Test SSH to Linux VM

1. Open Command Prompt or Terminal
2. Run the SSH command:

ssh azureuser@[LinuxVM-Public-IP]
# Password: LabPassword123!

3. Expected Result: ✅ Successful SSH connection

Step 5: Verify Network Configuration

From within each VM, verify the network setup:

Windows VM (Command Prompt):

# Check network configuration
ipconfig /all

# Test internet connectivity
ping 8.8.8.8

Linux VM (Terminal):

# Check network configuration
ip addr show

# Test internet connectivity
ping -c 4 8.8.8.8

# Check routing
ip route show

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Part 5: Advanced Configuration & Testing

Step 1: Test DNS Resolution

If you configured DNS name labels, test FQDN access:

# Test with FQDN instead of IP
ssh azureuser@winvm-[your-initials]-[random].[region].cloudapp.azure.com

Step 2: Modify Public IP Properties

1. Navigate to WinVM-PublicIP
2. Click Configuration in the left menu
3. Experiment with settings:

Setting	Options	Impact
Assignment	Static vs Dynamic	IP persistence
Idle timeout	4-30 minutes	Connection timeout
DNS name label	Custom name	FQDN availability

Step 3: Monitor Public IP Usage

1. In WinVM-PublicIP, click Metrics
2. View available metrics:
   • Bytes In/Out
   • Packets In/Out
   • Port counts

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🔧 Troubleshooting Guide

Common Issues and Solutions

Issue	Possible Cause	Solution
Can’t attach NIC to VM	VM not fully stopped	Ensure VM shows “Stopped (deallocated)“
RDP connection fails	NSG rule missing/incorrect	Verify RDP rule allows your IP
SSH connection fails	Wrong credentials/NSG	Check SSH rule and credentials
No internet from VM	Route table issues	Check default route exists
Public IP not accessible	NSG blocking traffic	Review inbound security rules

NSG Rule Verification

Protocol	Port	Source	Action
RDP	3389	Your IP	Allow
SSH	22	Your IP	Allow
HTTP	80	Any (optional)	Allow
HTTPS	443	Any (optional)	Allow

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🧪 Additional Experiments

Try these optional exercises to deepen your understanding:

1. Multiple NICs: Attach additional NICs to VMs
2. Basic vs Standard SKU: Compare different Public IP SKUs
3. IPv6 Support: Configure IPv6 public addresses
4. Load Balancer Integration: Use Public IPs with load balancers
5. NAT Gateway: Implement outbound-only connectivity

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🎓 Key Takeaways

After completing this lab, you should understand:

• Public IP addresses enable internet connectivity to Azure VMs
• NICs (Network Interface Cards) connect VMs to virtual networks
• NSG rules control traffic to public-facing resources
• Standard SKU provides enhanced features and availability
• Static assignment ensures IP addresses don’t change
• DNS name labels provide user-friendly FQDNs
• Security configuration is critical for public-facing resources

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📊 Public IP Configuration Summary

SKU Comparison

Feature	Basic SKU	Standard SKU
Assignment methods	Dynamic, Static	Static only
Security	Open by default	Secure by default (NSG required)
Availability zones	Not supported	Supported
Load balancer support	Basic LB only	Basic + Standard LB
Cost	Lower	Higher

Allocation Methods

• Static: IP address assigned permanently
• Dynamic: IP address may change when VM is deallocated

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📚 Additional Resources

• Public IP Addresses Overview
• Network Interface Overview
• NSG Security Rules
• Azure Networking Best Practices