URL maps for routing in GCP - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ service_behavior

intermediate

How does a URL map route traffic based on host rules?

Consider a URL map configured with two host rules: one for example.com routing to backend service A, and another for test.com routing to backend service B. What happens when a request is sent to example.com?

A The request is rejected because only test.com is configured in the URL map.

B The request is routed to backend service B because test.com is the default host.

C The request is routed to a random backend service because host rules do not affect routing.

D The request is routed to backend service A because the host matches example.com.

💡 Hint

Think about how host rules match the domain name in the request.

URL maps use host rules to match the domain name in the incoming request. If the host matches example.com, the request is routed to the backend service assigned to that host rule.

❓ Configuration

intermediate

What is the effect of path matchers in a URL map?

A URL map has a path matcher that routes requests with path /images/* to backend service Images, and all other paths to backend service Default. What backend service handles a request to /images/logo.png?

A Backend service Default, because /images/logo.png is not an exact match.

B Backend service Images, but only if the host matches a specific host rule.

C Backend service Images, because the path matches /images/*.

D The request is rejected because no exact path match exists.

💡 Hint

Consider how path matchers use wildcard patterns.

Path matchers use wildcard patterns to match request paths. The pattern /images/* matches any path starting with /images/, so /images/logo.png matches and routes to backend service Images.

❓ Architecture

advanced

How to design a URL map for multi-region backend routing?

You want to route users to backend services in different regions based on URL path prefixes: /us/* to US backend, /eu/* to EU backend, and all others to a global backend. Which URL map configuration achieves this?

A Create separate URL maps for each region and use DNS to route users.

B Create path matchers for /us/* routing to US backend, /eu/* routing to EU backend, and a default path matcher routing to global backend.

C Use host rules to route /us/* and /eu/* paths to respective backends.

D Configure backend services to detect user location and redirect requests.

💡 Hint

Think about how path matchers can route based on URL paths.

URL maps can use path matchers with wildcard paths to route requests to different backends based on URL prefixes. This allows routing /us/* to US backend, /eu/* to EU backend, and all others to a global backend.

❓ security

advanced

What happens if a URL map has no default backend service configured?

A URL map is created with host and path rules but no default backend service. What is the expected behavior when a request does not match any host or path rule?

A The request is rejected with a 404 Not Found error.

B The request is routed to the first backend service defined in the URL map.

C The request is routed to a global default backend service automatically.

D The request is redirected to the root path of the first host rule.

💡 Hint

Consider what happens when no matching rule exists and no default is set.

If no default backend service is configured, and the request does not match any host or path rule, the load balancer returns a 404 Not Found error because it does not know where to send the request.

✅ Best Practice

expert

How to optimize URL map configuration for minimal latency in global load balancing?

You manage a global HTTP(S) load balancer with multiple backend services worldwide. Which URL map design best reduces latency for users worldwide?

A Use host and path rules to route requests to backend services closest to the user's region, combined with Cloud CDN for caching.

B Route all requests to a single global backend service to simplify configuration.

C Use only host rules without path matchers to reduce URL map complexity.

D Configure URL maps to route based on IP address ranges instead of URL paths.

💡 Hint

Think about combining routing and caching to improve latency.

Routing users to the nearest backend service using host and path rules reduces latency. Adding Cloud CDN caches content closer to users, further improving response times.