Load balancing rules in Azure - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the protocol for the load balancing rule.

Azure

load_balancer_rule = {
  "name": "myLoadBalancingRule",
  "protocol": "[1]",
  "frontendPort": 80,
  "backendPort": 80
}

Drag options to blanks, or click blank then click option'

AUDP

BTCP

CHTTP

DFTP

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing UDP when the service requires reliable connection.

Using application protocols like HTTP instead of transport protocols.

The protocol for load balancing rules is typically set to TCP or UDP. Here, TCP is the correct choice for HTTP traffic.

2fill in blank

medium

Complete the code to set the frontend port for the load balancing rule.

Azure

load_balancer_rule = {
  "name": "myLoadBalancingRule",
  "protocol": "TCP",
  "frontendPort": [1],
  "backendPort": 80
}

Drag options to blanks, or click blank then click option'

A22

B8080

C443

D80

Attempts:

3 left

💡 Hint

Common Mistakes

Using port 22 which is for SSH.

Confusing frontend and backend ports.

The frontend port is the port on which the load balancer listens. Port 80 is standard for HTTP traffic.

3fill in blank

hard

Fix the error in the load balancing rule by completing the backend port correctly.

Azure

load_balancer_rule = {
  "name": "myLoadBalancingRule",
  "protocol": "TCP",
  "frontendPort": 80,
  "backendPort": [1]
}

Drag options to blanks, or click blank then click option'

A22

B443

C80

D21

Attempts:

3 left

💡 Hint

Common Mistakes

Setting backend port to SSH or FTP ports.

Mismatching frontend and backend ports.

The backend port should match the port on which the backend servers listen. For HTTP, this is usually port 80.

4fill in blank

hard

Fill both blanks to configure the load balancing rule with the correct frontend IP configuration and idle timeout.

Azure

load_balancer_rule = {
  "name": "myLoadBalancingRule",
  "frontendIPConfiguration": [1],
  "idleTimeoutInMinutes": [2]
}

Drag options to blanks, or click blank then click option'

A"frontendIPConfig1"

B"backendIPConfig1"

C4

D30

Attempts:

3 left

💡 Hint

Common Mistakes

Using backend IP config for frontend IP configuration.

Setting idle timeout too low causing premature disconnections.

The frontend IP configuration must reference the frontend IP, here "frontendIPConfig1". The idle timeout is commonly set to 30 minutes to keep connections alive.

5fill in blank

hard

Fill all three blanks to complete the load balancing rule with correct protocol, load distribution, and enable floating IP.

Azure

load_balancer_rule = {
  "name": "myLoadBalancingRule",
  "protocol": "[1]",
  "loadDistribution": "[2]",
  "enableFloatingIP": [3]
}

Drag options to blanks, or click blank then click option'

ATCP

BSourceIP

Ctrue

DUDP

Attempts:

3 left

💡 Hint

Common Mistakes

Using UDP when TCP is required.

Disabling floating IP when needed for certain scenarios.

The protocol is set to TCP for reliable connections. Load distribution by SourceIP ensures requests from the same client go to the same backend. Floating IP enabled (true) allows direct server return traffic.

Practice

1. What is the main purpose of a load balancing rule in Azure Load Balancer?

easy

A. To create virtual machines automatically

B. To store data securely in the cloud

C. To distribute incoming network traffic evenly across backend servers

D. To monitor user activity on a website

Solution

1. Step 1: Understand load balancing rules

   Load balancing rules define how traffic is distributed from the frontend IP to backend servers.

2. Step 2: Identify the main function

   The main function is to spread incoming traffic evenly to avoid overloading one server.

3. Final Answer:

   To distribute incoming network traffic evenly across backend servers -> Option C

4. Quick Check:

   Load balancing rules = distribute traffic evenly [OK]

Hint: Load balancing rules spread traffic evenly to backend servers [OK]

Common Mistakes:

• Confusing load balancing with VM creation
• Thinking it stores data
• Assuming it tracks user activity

2. Which of the following is the correct way to specify a load balancing rule's frontend port in Azure CLI?

easy

A. --frontend-port 80

B. --frontendPort 80

C. --front-port 80

D. --port-frontend 80

Solution

1. Step 1: Review Azure CLI syntax for load balancing rules

   The correct parameter for frontend port is '--frontend-port' with a hyphen.

2. Step 2: Compare options

   Only --frontend-port 80 uses the exact correct syntax '--frontend-port 80'. Others have incorrect parameter names.

3. Final Answer:

   --frontend-port 80 -> Option A

4. Quick Check:

   Azure CLI frontend port = --frontend-port [OK]

Hint: Azure CLI uses hyphenated parameters like --frontend-port [OK]

Common Mistakes:

• Using camelCase instead of hyphens
• Mixing words order in parameter
• Using incorrect parameter names

3. Given this Azure Load Balancer rule configuration snippet:

"frontendPort": 443,
"backendPort": 8443,
"protocol": "Tcp"

What happens when a user sends a TCP request to port 443 on the frontend IP?

medium

A. The request is forwarded to backend servers on port 8443

B. The request is blocked because ports do not match

C. The request is forwarded to backend servers on port 443

D. The request is forwarded using UDP protocol

Solution

1. Step 1: Understand frontend and backend ports in load balancing

   The frontend port is where the client connects; the backend port is where the traffic is sent on backend servers.

2. Step 2: Match the ports and protocol

   Client connects to port 443 (frontend), traffic is forwarded to backend servers on port 8443 using TCP.

3. Final Answer:

   The request is forwarded to backend servers on port 8443 -> Option A

4. Quick Check:

   Frontend port 443 forwards to backend port 8443 [OK]

Hint: Frontend port ≠ backend port; traffic forwards to backend port [OK]

Common Mistakes:

• Assuming frontend and backend ports must be the same
• Confusing TCP with UDP protocol
• Thinking request is blocked due to port difference

4. You created a load balancing rule but traffic is not reaching backend servers. Which of these is a likely misconfiguration?

medium

A. Load balancing rule uses correct protocol and ports

B. Frontend IP address is set correctly

C. Backend pool contains healthy servers

D. Health probe is missing or misconfigured

Solution

1. Step 1: Check role of health probes

   Health probes monitor backend server health; without them, load balancer may not send traffic.

2. Step 2: Identify misconfiguration

   If health probe is missing or wrong, backend servers appear unhealthy, so traffic is blocked.

3. Final Answer:

   Health probe is missing or misconfigured -> Option D

4. Quick Check:

   Missing health probe blocks traffic [OK]

Hint: Always configure health probes to allow traffic flow [OK]

Common Mistakes:

• Ignoring health probe setup
• Assuming backend servers are always healthy
• Overlooking frontend IP correctness

5. You want to create a load balancing rule that forwards HTTPS traffic from port 443 on the frontend IP to port 8443 on backend VMs, but only if the backend VMs pass a TCP health probe on port 8443. Which configuration is correct?

hard

A. Load balancing rule with frontendPort=8443, backendPort=443, protocol=Tcp; health probe on port 443 using Http

B. Load balancing rule with frontendPort=443, backendPort=8443, protocol=Tcp; health probe on port 8443 using Tcp

C. Load balancing rule with frontendPort=443, backendPort=443, protocol=Udp; health probe on port 8443 using Tcp

D. Load balancing rule with frontendPort=443, backendPort=8443, protocol=Tcp; no health probe configured

Solution

1. Step 1: Match frontend and backend ports with protocol

   Frontend port 443 (HTTPS) forwards to backend port 8443 using TCP protocol, matching the requirement.

2. Step 2: Configure health probe correctly

   Health probe must check TCP on port 8443 to verify backend VM health before forwarding traffic.

3. Step 3: Verify other options

   Load balancing rule with frontendPort=8443, backendPort=443, protocol=Tcp; health probe on port 443 using Http swaps ports and uses HTTP probe incorrectly; Load balancing rule with frontendPort=443, backendPort=443, protocol=Udp; health probe on port 8443 using Tcp uses UDP protocol wrongly; Load balancing rule with frontendPort=443, backendPort=8443, protocol=Tcp; no health probe configured lacks health probe, risking traffic to unhealthy VMs.

4. Final Answer:

   Load balancing rule with frontendPort=443, backendPort=8443, protocol=Tcp; health probe on port 8443 using Tcp -> Option B

5. Quick Check:

   Correct ports, protocol, and health probe = Load balancing rule with frontendPort=443, backendPort=8443, protocol=Tcp; health probe on port 8443 using Tcp [OK]

Hint: Match frontend/backend ports and use health probe on backend port [OK]

Common Mistakes:

• Swapping frontend and backend ports
• Using wrong protocol (UDP instead of TCP)
• Skipping health probe configuration