Azure CDN profiles and endpoints - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Azure CDN Profiles

Which statement best describes the purpose of an Azure CDN profile?

A It groups multiple CDN endpoints under a single management scope and billing account.

B It stores the cached content delivered by the CDN to end users.

C It is the configuration for a single domain name used by the CDN.

D It defines the geographic locations where CDN nodes are deployed.

💡 Hint

Think about how Azure organizes CDN resources for billing and management.

An Azure CDN profile acts as a container for multiple CDN endpoints, allowing centralized management and billing. It does not store content or define node locations directly.

❓ Architecture

intermediate

Azure CDN Endpoint Configuration

You want to deliver static website content globally using Azure CDN. Which component must you create to specify the origin server for your content?

A Azure CDN endpoint

B Azure CDN profile

C Azure CDN custom domain

D Azure CDN caching rule

💡 Hint

Consider which part connects the CDN to your source content.

The Azure CDN endpoint defines the origin server URL from which the CDN pulls content to cache and deliver to users.

❓ scaling

advanced

Scaling Azure CDN for High Traffic

Your website experiences sudden spikes in traffic worldwide. Which Azure CDN feature helps ensure low latency and high availability during these spikes?

A Multiple CDN profiles with separate billing

B Using multiple CDN endpoints within a profile to distribute load

C Configuring a single CDN endpoint with a custom domain

D Enabling geo-filtering to restrict traffic

💡 Hint

Think about how to distribute traffic load efficiently.

Using multiple CDN endpoints within a profile allows traffic to be distributed across endpoints, improving load handling and availability during spikes.

❓ tradeoff

advanced

Choosing Between CDN Providers in Azure

Azure CDN supports multiple providers like Verizon and Microsoft. What is a key tradeoff when selecting a CDN provider for your Azure CDN profile?

A Verizon CDN provides advanced security features but may have higher latency in some regions.

B Microsoft CDN offers more global POPs but less integration with Azure services.

C Choosing a provider affects pricing, feature set, and geographic coverage.

D All providers offer identical features and pricing, so choice is irrelevant.

💡 Hint

Consider differences in cost, features, and coverage.

Each CDN provider has unique pricing, features, and geographic reach, so selecting one involves balancing these factors based on your needs.

❓ estimation

expert

Estimating Azure CDN Endpoint Capacity

You expect 10 million requests per day globally with an average response size of 500 KB. Approximately how much data transfer (in TB) will your Azure CDN endpoint handle daily?

A About 0.5 TB

B About 50 TB

C About 500 TB

D About 5 TB

💡 Hint

Calculate total bytes transferred: requests × size, then convert to TB (1 TB = 10^12 bytes).

10 million requests × 500 KB = 5,000,000,000 KB = 5,000,000,000,000 bytes = 5 TB.

Practice

1. What is the primary purpose of an Azure CDN profile?

easy

A. To manage user authentication

B. To store website content directly

C. To group CDN endpoints and define pricing tiers

D. To create virtual machines

Solution

1. Step 1: Understand the role of a CDN profile

   An Azure CDN profile acts as a container for one or more CDN endpoints and defines the pricing and features for those endpoints.

2. Step 2: Differentiate from other Azure services

   Profiles do not store content or manage authentication; those are handled by other Azure services.

3. Final Answer:

   To group CDN endpoints and define pricing tiers -> Option C

4. Quick Check:

   CDN profile = group endpoints + pricing [OK]

Hint: Profiles group endpoints and set pricing tiers [OK]

Common Mistakes:

• Confusing profiles with storage accounts
• Thinking profiles manage user access
• Assuming profiles store content

2. Which of the following is the correct way to create a new Azure CDN endpoint under an existing profile using Azure CLI?

easy

A. az cdn profile create --name myEndpoint --resource-group myResourceGroup --origin myOrigin

B. az cdn endpoint create --name myEndpoint --profile-name myProfile --resource-group myResourceGroup --origin myOrigin

C. az storage account create --name myEndpoint --profile myProfile

D. az vm create --name myEndpoint --profile myProfile

Solution

1. Step 1: Identify the correct Azure CLI command for endpoint creation

   The command to create a CDN endpoint is az cdn endpoint create with parameters for name, profile, resource group, and origin.

2. Step 2: Eliminate incorrect commands

   The other options use commands for profile creation, storage account creation, and virtual machine creation, which are unrelated to endpoint creation.

3. Final Answer:

   az cdn endpoint create --name myEndpoint --profile-name myProfile --resource-group myResourceGroup --origin myOrigin -> Option B

4. Quick Check:

   Endpoint creation uses az cdn endpoint create [OK]

Hint: Use 'az cdn endpoint create' with profile and origin [OK]

Common Mistakes:

• Using profile create command instead of endpoint create
• Confusing storage or VM commands with CDN commands
• Omitting required parameters like origin

3. Given an Azure CDN endpoint configured with origin mywebsite.azurewebsites.net, what happens when a user requests a file not yet cached by the CDN?

medium

A. The CDN fetches the file from the origin and caches it for future requests

B. The CDN returns a 404 error immediately

C. The CDN redirects the user to the origin URL

D. The CDN serves a default placeholder file

Solution

1. Step 1: Understand CDN cache miss behavior

   When a requested file is not in the CDN cache, the CDN fetches it from the origin server.

2. Step 2: Explain caching for future requests

   After fetching, the CDN caches the file to serve subsequent requests faster and reduce load on the origin.

3. Final Answer:

   The CDN fetches the file from the origin and caches it for future requests -> Option A

4. Quick Check:

   Cache miss = fetch + cache [OK]

Hint: Cache miss triggers origin fetch and caching [OK]

Common Mistakes:

• Assuming CDN returns error on cache miss
• Thinking CDN redirects to origin URL
• Believing CDN serves placeholder files

4. You created an Azure CDN endpoint but users report stale content is served after you updated your origin. What is the most likely cause and fix?

medium

A. The CDN profile is deleted; recreate the profile

B. The origin server is down; restart the origin server

C. The endpoint URL is incorrect; update DNS settings

D. The CDN cache is not refreshed; purge the CDN endpoint cache

Solution

1. Step 1: Identify cause of stale content

   CDNs cache content to improve speed, so updates at origin may not appear immediately due to cached copies.

2. Step 2: Apply the fix by purging cache

   Purging the CDN endpoint cache forces the CDN to fetch fresh content from the origin on next requests.

3. Final Answer:

   The CDN cache is not refreshed; purge the CDN endpoint cache -> Option D

4. Quick Check:

   Stale content = cache purge needed [OK]

Hint: Purge CDN cache to update stale content [OK]

Common Mistakes:

• Restarting origin when issue is cache
• Recreating profile unnecessarily
• Changing DNS when endpoint URL is correct

5. You want to design a scalable global content delivery system using Azure CDN. Which combination of Azure CDN features and configurations best supports low latency and high availability?

hard

A. Create multiple CDN endpoints in different regions under one profile; enable geo-filtering and custom domain HTTPS

B. Use a single CDN endpoint with default settings; rely on origin scaling

C. Create multiple CDN profiles with one endpoint each; disable caching to always fetch from origin

D. Use Azure Blob Storage directly without CDN; enable CDN only for static files

Solution

1. Step 1: Understand global scalability needs

   Multiple CDN endpoints in different regions reduce latency by serving users from nearest edge locations.

2. Step 2: Use features for availability and security

   Geo-filtering controls content delivery by region; custom domain HTTPS secures traffic and improves trust.

3. Step 3: Evaluate other options

   Single endpoint or disabling caching reduces performance; multiple profiles add complexity without benefit; skipping CDN loses caching advantages.

4. Final Answer:

   Create multiple CDN endpoints in different regions under one profile; enable geo-filtering and custom domain HTTPS -> Option A

5. Quick Check:

   Multiple endpoints + geo-filter + HTTPS = scalable, low latency [OK]

Hint: Multiple endpoints + geo-filtering + HTTPS for global scale [OK]

Common Mistakes:

• Using single endpoint for global users
• Disabling caching reduces performance
• Ignoring HTTPS security best practices