Host-based routing in Kubernetes - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the host for routing in the Ingress rule.

Kubernetes

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: example-ingress
spec:
  rules:
  - host: [1]
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: example-service
            port:
              number: 80

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

Aexample-service

B80

C/

Dexample.com

Attempts:

3 left

💡 Hint

Common Mistakes

Using the service name instead of the host domain.

Putting the port number in the host field.

The host field specifies the domain name for host-based routing in the Ingress rule.

2fill in blank

medium

Complete the code to specify the path type for host-based routing.

Kubernetes

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: example-ingress
spec:
  rules:
  - host: example.com
    http:
      paths:
      - path: /app
        pathType: [1]
        backend:
          service:
            name: app-service
            port:
              number: 80

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

AExact

BSuffix

CPrefix

DContains

Attempts:

3 left

💡 Hint

Common Mistakes

Using unsupported path types like Suffix or Contains.

Confusing Exact with Prefix.

The pathType defines how the path is matched. Prefix means any path starting with /app will match.

3fill in blank

hard

Fix the error in the Ingress rule to correctly specify the backend service port.

Kubernetes

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: example-ingress
spec:
  rules:
  - host: example.com
    http:
      paths:
      - path: /api
        pathType: Prefix
        backend:
          service:
            name: api-service
            port:
              [1]

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

Anumber: 80

B80

Cport: 80

Dname: 80

Attempts:

3 left

💡 Hint

Common Mistakes

Using just the port number without the 'number:' key.

Using 'port: 80' directly instead of nested object.

The port field must be an object with a number key specifying the port number.

4fill in blank

hard

Fill both blanks to create a host-based routing rule for two different hosts.

Kubernetes

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: multi-host-ingress
spec:
  rules:
  - host: [1]
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: service-one
            port:
              number: 80
  - host: [2]
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: service-two
            port:
              number: 80

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

Aapp1.example.com

Bapp2.example.com

Cexample.com

Dservice.example.com

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same host for both rules.

Using service names instead of domain names.

Each host field must have a unique domain name for routing to different services.

5fill in blank

hard

Fill all three blanks to define an Ingress with host-based routing, path, and backend service port.

Kubernetes

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: full-ingress
spec:
  rules:
  - host: [1]
    http:
      paths:
      - path: [2]
        pathType: Prefix
        backend:
          service:
            name: full-service
            port:
              number: [3]

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

Amyapp.example.com

B/dashboard

C8080

D/api

Attempts:

3 left

💡 Hint

Common Mistakes

Using a path without leading slash.

Using a string instead of a number for port.

Confusing host with service name.

The host is the domain name, path is the URL path prefix, and number is the backend service port.

Practice

1. What is the main purpose of host-based routing in Kubernetes Ingress?

easy

A. To encrypt all incoming traffic automatically.

B. To balance traffic evenly across all nodes in the cluster.

C. To monitor the health of backend services.

D. To send traffic to different services based on the website address (host).

Solution

1. Step 1: Understand host-based routing concept

   Host-based routing directs requests to services depending on the host name in the URL.

2. Step 2: Compare options to the concept

   Only To send traffic to different services based on the website address (host). matches this behavior; others describe different features.

3. Final Answer:

   To send traffic to different services based on the website address (host). -> Option D

4. Quick Check:

   Host-based routing = directing traffic by host [OK]

Hint: Host-based routing uses website address to choose service [OK]

Common Mistakes:

• Confusing host-based routing with load balancing
• Thinking it encrypts traffic automatically
• Assuming it monitors service health

2. Which of the following is the correct way to specify host-based routing in a Kubernetes Ingress YAML?

easy

A. spec:
host: example.com
paths:
- path: /
serviceName: my-service
servicePort: 80

B. spec:
rules:
- host: example.com
http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: my-service
port:
number: 80

C. metadata:
host: example.com
spec:
service:
name: my-service
port: 80

D. spec:
rules:
- path: example.com
backend:
serviceName: my-service
servicePort: 80

Solution

1. Step 1: Review Kubernetes Ingress host-based routing syntax

   The correct syntax uses 'rules' with 'host' and 'http.paths' specifying backend service details.

2. Step 2: Match options to correct syntax

   spec: rules: - host: example.com http: paths: - path: / pathType: Prefix backend: service: name: my-service port: number: 80 matches the official Kubernetes Ingress spec format for host-based routing.

3. Final Answer:

   spec: rules: - host: example.com http: paths: - path: / pathType: Prefix backend: service: name: my-service port: number: 80 -> Option B

4. Quick Check:

   Correct Ingress host syntax = spec: rules: - host: example.com http: paths: - path: / pathType: Prefix backend: service: name: my-service port: number: 80 [OK]

Hint: Look for 'rules' with 'host' and 'http.paths' in Ingress YAML [OK]

Common Mistakes:

• Placing 'host' under metadata instead of rules
• Using deprecated 'serviceName' and 'servicePort' keys
• Confusing 'path' with 'host' field

3. Given this Ingress rule snippet, what service will receive traffic for host 'app.example.com'?

spec:
  rules:
  - host: app.example.com
    http:
      paths:
      - path: /app
        pathType: Prefix
        backend:
          service:
            name: app-service
            port:
              number: 8080
      - path: /
        pathType: Prefix
        backend:
          service:
            name: default-service
            port:
              number: 80

medium

A. Traffic to app.example.com with path starting /app goes to app-service; others go to default-service.

B. Traffic to app.example.com is rejected because of duplicate host rules.

C. Traffic to app.example.com goes only to default-service on port 80.

D. All traffic to app.example.com goes to app-service on port 8080.

Solution

1. Step 1: Analyze the Ingress rules for host 'app.example.com'

   The rule for host 'app.example.com' has two paths: '/app' and '/'.

2. Step 2: Understand path matching priority

   Requests with path starting '/app' go to 'app-service' on port 8080; all other paths go to 'default-service' on port 80.

3. Final Answer:

   Traffic to app.example.com with path starting /app goes to app-service; others go to default-service. -> Option A

4. Quick Check:

   Host + path routing = Traffic to app.example.com with path starting /app goes to app-service; others go to default-service. [OK]

Hint: Check host and path rules separately to find matching service [OK]

Common Mistakes:

• Assuming all traffic goes to first service listed
• Thinking duplicate hosts cause rejection
• Ignoring path prefixes in routing

4. You created this Ingress YAML but traffic to 'shop.example.com' is not routed correctly. What is the error?

spec:
  rules:
  - host: shop.example.com
    http:
      paths:
      - path: /shop
        backend:
          serviceName: shop-service
          servicePort: 80

medium

A. The keys 'serviceName' and 'servicePort' are deprecated; use 'service.name' and 'service.port.number'.

B. The host field is missing under metadata.

C. The path should be '/' instead of '/shop'.

D. The Ingress resource must have a selector field.

Solution

1. Step 1: Check Ingress backend service syntax

   Modern Kubernetes Ingress requires 'service.name' and 'service.port.number' keys, not 'serviceName' and 'servicePort'.

2. Step 2: Identify the error in YAML

   The YAML uses deprecated keys causing routing failure.

3. Final Answer:

   The keys 'serviceName' and 'servicePort' are deprecated; use 'service.name' and 'service.port.number'. -> Option A

4. Quick Check:

   Use correct backend service keys = The keys 'serviceName' and 'servicePort' are deprecated; use 'service.name' and 'service.port.number'. [OK]

Hint: Use 'service.name' and 'service.port.number' in Ingress backend [OK]

Common Mistakes:

• Using old 'serviceName' and 'servicePort' keys
• Adding host under metadata instead of rules
• Changing path unnecessarily

5. You want to run two websites, 'blog.example.com' and 'shop.example.com', on the same Kubernetes cluster using one Ingress. How should you configure the Ingress rules for host-based routing?

hard

A. Create one rule with host 'example.com' and use paths '/blog' and '/shop' to route to services.

B. Create separate Ingress resources for each host with identical paths.

C. Create two rules under spec.rules, each with a different host and paths pointing to their respective services.

D. Use a single rule with no host specified and rely on path prefixes only.

Solution

1. Step 1: Understand host-based routing for multiple hosts

   To route traffic by host, define separate rules for each host under spec.rules.

2. Step 2: Compare options for best practice

   Create two rules under spec.rules, each with a different host and paths pointing to their respective services. correctly uses two rules with different hosts and paths to route traffic properly.

3. Final Answer:

   Create two rules under spec.rules, each with a different host and paths pointing to their respective services. -> Option C

4. Quick Check:

   Multiple hosts need separate rules = Create two rules under spec.rules, each with a different host and paths pointing to their respective services. [OK]

Hint: Use separate rules for each host in one Ingress resource [OK]

Common Mistakes:

• Using one host with path prefixes instead of separate hosts
• Creating multiple Ingresses unnecessarily
• Not specifying hosts and relying on paths only