HTTP to HTTPS redirect in Nginx - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Configuration

intermediate

Basic HTTP to HTTPS Redirect Configuration

Which nginx server block configuration correctly redirects all HTTP requests to HTTPS?

Nginx

server {
    listen 80;
    server_name example.com www.example.com;

    # Redirect rule here
}

A return 301 https://$host$request_uri;

B proxy_pass https://$host$request_uri;

C rewrite ^ https://$host$request_uri permanent;

D error_page 301 https://$host$request_uri;

💡 Hint

Use a simple return directive for permanent redirect in nginx.

The return 301 https://$host$request_uri; directive sends a permanent redirect to the client, telling it to use HTTPS. The rewrite directive can also redirect but is more complex and less efficient here. proxy_pass is for forwarding requests, not redirecting. error_page is for error handling, not redirects.

💻 Command Output

intermediate

Output of curl Command for HTTP Redirect

You run the command curl -I http://example.com against an nginx server configured to redirect HTTP to HTTPS. What is the expected HTTP status code in the response headers?

A HTTP/1.1 301 Moved Permanently

B HTTP/1.1 500 Internal Server Error

C HTTP/1.1 404 Not Found

D HTTP/1.1 200 OK

💡 Hint

Permanent redirects use status code 301.

The curl -I command fetches headers only. When nginx redirects HTTP to HTTPS, it sends a 301 Moved Permanently status code to tell the client to use the HTTPS URL.

❓ Troubleshoot

advanced

Why is HTTP to HTTPS Redirect Not Working?

An nginx server block is configured to redirect HTTP to HTTPS, but when accessing http://example.com, the browser does not redirect and shows the HTTP content instead. Which is the most likely cause?

Nginx

server {
    listen 80;
    server_name example.com;
    # redirect missing or incorrect
}

server {
    listen 443 ssl;
    server_name example.com;
    ssl_certificate /path/to/cert.pem;
    ssl_certificate_key /path/to/key.pem;
    # HTTPS content
}

A The server_name directive is missing in the HTTPS block.

B The HTTP server block is missing the redirect directive.

C The HTTPS server block should listen on port 80.

D The SSL certificate is expired, so redirect fails.

💡 Hint

Check if the HTTP block actually tells nginx to redirect.

If the HTTP server block does not have a redirect directive, nginx will serve HTTP content normally without redirecting. SSL certificate issues or server_name missing in HTTPS block do not affect HTTP redirect. HTTPS block listening on port 80 is incorrect.

🔀 Workflow

advanced

Order of Steps to Enable HTTP to HTTPS Redirect in nginx

Arrange the steps in the correct order to enable HTTP to HTTPS redirect on an nginx server.

A 3,1,2,4

B 1,3,2,4

C 2,1,3,4

D 1,2,3,4

💡 Hint

Think about what must be done before configuring SSL and redirects.

First, you must have a valid SSL certificate (step 1). Then configure the HTTP block to redirect (step 2) and the HTTPS block with SSL (step 3). Finally, reload nginx to apply changes (step 4).

✅ Best Practice

expert

Best Practice for Handling www and non-www Redirects with HTTPS

You want to redirect all HTTP and HTTPS requests to the HTTPS version with www.example.com. Which nginx configuration snippet correctly implements this best practice?

A

server {
    listen 80;
    server_name example.com;
    return 301 https://example.com$request_uri;
}

server {
    listen 443 ssl;
    server_name www.example.com;
    ssl_certificate /path/to/cert.pem;
    ssl_certificate_key /path/to/key.pem;
    # main site content
}

B

server {
    listen 80;
    server_name www.example.com;
    return 301 https://www.example.com$request_uri;
}

server {
    listen 443 ssl;
    server_name example.com www.example.com;
    ssl_certificate /path/to/cert.pem;
    ssl_certificate_key /path/to/key.pem;
    # main site content
}

C

server {
    listen 80;
    server_name example.com www.example.com;
    return 301 https://www.example.com$request_uri;
}

server {
    listen 443 ssl;
    server_name example.com;
    return 301 https://www.example.com$request_uri;
    ssl_certificate /path/to/cert.pem;
    ssl_certificate_key /path/to/key.pem;
}

server {
    listen 443 ssl;
    server_name www.example.com;
    ssl_certificate /path/to/cert.pem;
    ssl_certificate_key /path/to/key.pem;
    # main site content
}

D

server {
    listen 80;
    server_name example.com www.example.com;
    return 301 https://$host$request_uri;
}

server {
    listen 443 ssl;
    server_name example.com www.example.com;
    ssl_certificate /path/to/cert.pem;
    ssl_certificate_key /path/to/key.pem;
    # main site content
}

💡 Hint

Redirect all variants to a single canonical HTTPS domain with www.

Option C redirects all HTTP requests and HTTPS requests for example.com to https://www.example.com. This ensures a single canonical URL with HTTPS and www. Other options either do not redirect non-www HTTPS or redirect to non-www HTTPS, which is not the best practice here.