Public IP addresses in Azure - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a Public IP address in Azure?

A Public IP address in Azure is an address that allows resources to communicate with the internet or other external networks. It is assigned to Azure resources like virtual machines or load balancers to enable inbound and outbound internet connectivity.

beginner

What are the two types of Public IP addresses in Azure?

Azure offers two types of Public IP addresses: Dynamic and Static. Dynamic IP addresses can change when the resource is stopped and started again, while Static IP addresses remain fixed for the lifetime of the resource.

intermediate

Why would you choose a Static Public IP address over a Dynamic one?

You choose a Static Public IP address when you need a fixed IP that does not change, such as for DNS records, firewall rules, or when clients need to reliably connect to your resource.

beginner

How does Azure assign a Dynamic Public IP address?

Azure assigns a Dynamic Public IP address from a pool of available addresses when the resource is started. This IP can change if the resource is stopped and started again.

intermediate

Can a Public IP address be associated with multiple Azure resources at the same time?

No, a Public IP address in Azure can only be associated with one resource at a time, such as a virtual machine, load balancer, or application gateway.

Which type of Public IP address in Azure remains the same even after restarting the resource?

A Static

B Dynamic

C Temporary

D Ephemeral

Static Public IP addresses remain fixed and do not change when the resource restarts.

What is the main purpose of assigning a Public IP address to an Azure virtual machine?

A To secure the VM from all traffic

B To increase the VM's CPU power

C To allow the VM to communicate with the internet

D To store data persistently

A Public IP address allows the VM to send and receive traffic from the internet.

If you stop and start a VM with a Dynamic Public IP, what happens to the IP address?

A It is deleted permanently

B It stays the same

C It becomes static automatically

D It may change

Dynamic Public IP addresses can change when the resource is stopped and started.

Can you assign the same Public IP address to two different Azure resources at the same time?

A No

B Yes, always

C Only if they are in different regions

D Only for load balancers

A Public IP address can only be associated with one resource at a time.

Which Azure service commonly uses Public IP addresses to distribute traffic?

A Azure Blob Storage

B Load Balancer

C Azure Functions

D Azure SQL Database

Azure Load Balancers use Public IP addresses to distribute incoming traffic to backend resources.

Explain what a Public IP address is in Azure and why it is important.

Think about how devices connect to the internet.

Describe the difference between Static and Dynamic Public IP addresses in Azure and when to use each.

Consider reliability and scenarios needing fixed addresses.

Practice

1.

What is the main purpose of a Public IP address in Azure?

easy

A. To allow cloud resources to connect to the internet

B. To secure internal communication within a virtual network

C. To store data securely in the cloud

D. To monitor resource usage and billing

Solution

1. Step 1: Understand Public IP role

   Public IP addresses enable resources to communicate over the internet.

2. Step 2: Compare options

   Only To allow cloud resources to connect to the internet describes internet connectivity, others describe unrelated functions.

3. Final Answer:

   To allow cloud resources to connect to the internet -> Option A

4. Quick Check:

   Public IP = Internet access [OK]

Hint: Public IP means internet access for resources [OK]

Common Mistakes:

• Confusing Public IP with internal network IP
• Thinking Public IP stores data
• Mixing Public IP with monitoring tools

2.

Which option correctly defines a Static Public IP address in Azure?

publicIpAllocationMethod: ?

easy

A. "Fixed"

B. "Dynamic"

C. "Manual"

D. "Static"

Solution

1. Step 1: Recall allocation methods

   Azure uses "Static" and "Dynamic" as valid allocation methods for Public IPs.

2. Step 2: Identify correct syntax

   "Static" is the exact string to assign for fixed IP allocation.

3. Final Answer:

   "Static" -> Option D

4. Quick Check:

   Static = fixed IP allocation [OK]

Hint: Static means fixed IP, use exact string "Static" [OK]

Common Mistakes:

• Using "Manual" or "Fixed" which are invalid values
• Confusing "Dynamic" with static allocation
• Omitting quotes around the string

3.

Given this Azure CLI command, what will be the SKU of the created Public IP?

az network public-ip create --name MyIP --resource-group MyGroup --sku Standard --allocation-method Static

medium

A. Standard

B. Basic

C. Premium

D. Dynamic

Solution

1. Step 1: Identify SKU parameter

   The command includes "--sku Standard", which sets the SKU to Standard.

2. Step 2: Understand SKU options

   Standard and Basic are common SKUs; Premium is not valid here, Dynamic is allocation method.

3. Final Answer:

   Standard -> Option A

4. Quick Check:

   --sku Standard means Standard SKU [OK]

Hint: Look for --sku value to find SKU type [OK]

Common Mistakes:

• Confusing allocation method with SKU
• Assuming default SKU is Basic without checking
• Selecting Dynamic which is not a SKU

4.

Identify the error in this Azure Resource Manager (ARM) template snippet for a Public IP:

{
  "type": "Microsoft.Network/publicIPAddresses",
  "apiVersion": "2021-02-01",
  "name": "myPublicIP",
  "properties": {
    "publicIPAllocationMethod": "Static",
    "sku": "Standard"
  }
}

medium

A. "name" must be inside "properties"

B. "sku" should be outside "properties" block

C. "publicIPAllocationMethod" value should be "Dynamic"

D. "apiVersion" is invalid

Solution

1. Step 1: Check ARM template structure

   In ARM templates, "sku" is a top-level property, not inside "properties".

2. Step 2: Validate other fields

   "publicIPAllocationMethod" can be "Static" inside properties; "name" is correctly placed; "apiVersion" is valid.

3. Final Answer:

   "sku" should be outside "properties" block -> Option B

4. Quick Check:

   SKU location in ARM = outside properties [OK]

Hint: "sku" is a sibling of "properties", not inside it [OK]

Common Mistakes:

• Placing "sku" inside properties
• Changing allocation method unnecessarily
• Misplacing "name" property

5.

You want a Public IP that never changes and offers better reliability for a production web app. Which combination should you choose?

hard

A. Dynamic allocation with Basic SKU

B. Static allocation with Basic SKU

C. Static allocation with Standard SKU

D. Dynamic allocation with Standard SKU

Solution

1. Step 1: Understand allocation methods

   Static allocation ensures the IP address does not change over time.

2. Step 2: Choose SKU for reliability

   Standard SKU provides better features and reliability than Basic SKU.

3. Step 3: Combine for production needs

   Static allocation with Standard SKU fits production web app requirements.

4. Final Answer:

   Static allocation with Standard SKU -> Option C

5. Quick Check:

   Static + Standard = fixed, reliable IP [OK]

Hint: Static + Standard SKU = fixed and reliable IP [OK]

Common Mistakes:

• Choosing Dynamic allocation for fixed IP needs
• Using Basic SKU for production reliability
• Mixing SKU and allocation method incorrectly