HTTP to HTTPS redirect in Nginx - Commands & Configuration

Introduction

Websites should use HTTPS to keep data safe. Redirecting HTTP to HTTPS makes sure visitors always use the secure version of the site without typing it manually.

When you want to protect user passwords and personal data on your website.

When you want to improve your website's trust and ranking on search engines.

When you want to avoid visitors seeing security warnings in their browsers.

When you have both HTTP and HTTPS enabled and want to force secure connections.

When you want to comply with security standards and regulations.

Config File - nginx.conf

nginx.conf

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 /etc/ssl/certs/example.com.crt;
    ssl_certificate_key /etc/ssl/private/example.com.key;

    location / {
        root /var/www/html;
        index index.html index.htm;
    }
}

The first server block listens on port 80 (HTTP) and redirects all requests to the same URL but with HTTPS using a 301 permanent redirect.

The second server block listens on port 443 (HTTPS) and serves the website content securely with SSL certificates.

Commands

Check the nginx configuration file for syntax errors before applying changes.

Terminal

sudo nginx -t

Expected Output

nginx: the configuration file /etc/nginx/nginx.conf syntax is ok

nginx: configuration file /etc/nginx/nginx.conf test is successful

Reload nginx to apply the new configuration without stopping the server.

Terminal

sudo systemctl reload nginx

Expected Output

No output (command runs silently)

Test the HTTP URL to verify it redirects to HTTPS with status code 301.

Terminal

curl -I http://example.com

Expected Output

HTTP/1.1 301 Moved Permanently

Server: nginx

Date: Wed, 01 Jan 2025 12:00:00 GMT

Content-Type: text/html

Content-Length: 178

Location: https://example.com/

Connection: keep-alive

Test the HTTPS URL to verify the site responds securely with status code 200.

Terminal

curl -I https://example.com

Expected Output

HTTP/1.1 200 OK

Server: nginx

Date: Wed, 01 Jan 2025 12:00:01 GMT

Content-Type: text/html

Content-Length: 612

Connection: keep-alive

Key Concept

If you remember nothing else from this pattern, remember: redirect all HTTP traffic to HTTPS using a 301 redirect to keep connections secure.

Common Mistakes

Not reloading nginx after changing the configuration.

The changes won't take effect until nginx reloads or restarts.

Always run 'sudo nginx -t' to check syntax, then 'sudo systemctl reload nginx' to apply changes.

Using a 302 temporary redirect instead of 301 permanent redirect.

Browsers and search engines may not update bookmarks or rankings properly with temporary redirects.

Use 'return 301 https://$host$request_uri;' for a permanent redirect.

Forgetting to configure SSL certificates in the HTTPS server block.

Without SSL certificates, HTTPS connections will fail or show security warnings.

Include valid 'ssl_certificate' and 'ssl_certificate_key' paths in the HTTPS server block.

Summary

Create an nginx server block listening on port 80 that redirects all HTTP requests to HTTPS with a 301 status.

Configure the HTTPS server block with SSL certificates to serve secure content on port 443.

Test the configuration syntax and reload nginx to apply changes without downtime.

Verify the redirect works by checking HTTP returns 301 and HTTPS returns 200 status codes.

Practice

1. What is the main purpose of configuring an HTTP to HTTPS redirect in nginx?

easy

A. To allow both HTTP and HTTPS traffic without changes

B. To block all HTTP traffic permanently

C. To automatically send users from an insecure HTTP site to a secure HTTPS site

D. To disable HTTPS and use only HTTP

Solution

1. Step 1: Understand HTTP and HTTPS roles

   HTTP is not secure, HTTPS encrypts data for safety.

2. Step 2: Purpose of redirect

   Redirecting HTTP to HTTPS ensures users always use the secure version.

3. Final Answer:

   To automatically send users from an insecure HTTP site to a secure HTTPS site -> Option C

4. Quick Check:

   Redirect HTTP to HTTPS = Secure site [OK]

Hint: Redirect HTTP to HTTPS to secure user connections [OK]

Common Mistakes:

• Thinking redirect blocks HTTP instead of forwarding
• Believing HTTPS disables HTTP completely
• Confusing redirect with allowing both protocols

2. Which nginx configuration snippet correctly redirects all HTTP requests to HTTPS?

easy

A. server { listen 80; rewrite ^ https://$host$uri permanent; }

B. server { listen 443 ssl; return 301 http://$host$request_uri; }

C. server { listen 80; proxy_pass https://$host$request_uri; }

D. server { listen 80; return 301 https://$host$request_uri; }

Solution

1. Step 1: Identify correct listen port and redirect method

   HTTP listens on port 80; redirect uses 'return 301' for permanent redirect.

2. Step 2: Check syntax correctness

   server { listen 80; return 301 https://$host$request_uri; } uses 'listen 80' and 'return 301 https://$host$request_uri;' which is correct syntax.

3. Final Answer:

   server { listen 80; return 301 https://$host$request_uri; } -> Option D

4. Quick Check:

   Port 80 + return 301 + https URL = Correct redirect [OK]

Hint: Use 'listen 80' and 'return 301 https://$host$request_uri;' [OK]

Common Mistakes:

• Using 'listen 443' for HTTP redirect
• Using 'proxy_pass' instead of 'return 301'
• Incorrect rewrite syntax causing errors

3. Given this nginx server block, what will happen when a user visits http://example.com/page?

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

medium

A. The user will see the HTTP version of the page without redirection

B. The user will be redirected to https://example.com/page with a permanent redirect

C. The server will return a 404 error

D. The server will proxy the request to HTTPS without changing the URL

Solution

1. Step 1: Analyze the server block

   It listens on port 80 (HTTP) and returns a 301 redirect to HTTPS version of the requested URI.

2. Step 2: Understand the redirect effect

   User visiting http://example.com/page will be sent a permanent redirect to https://example.com/page.

3. Final Answer:

   The user will be redirected to https://example.com/page with a permanent redirect -> Option B

4. Quick Check:

   HTTP request + return 301 to HTTPS = Redirect [OK]

Hint: Return 301 sends permanent redirect to HTTPS URL [OK]

Common Mistakes:

• Assuming no redirect happens
• Confusing proxy_pass with redirect
• Expecting error instead of redirect

4. You wrote this nginx config to redirect HTTP to HTTPS but it does not work:

server {
  listen 80;
  server_name example.com;
  rewrite ^ https://$host$uri permanent;
}

What is the likely problem?

medium

A. The rewrite directive should be replaced with 'return 301 https://$host$request_uri;'

B. The rewrite directive is missing a semicolon

C. The listen port should be 443 for HTTPS

D. The server_name directive is incorrect

Solution

1. Step 1: Check rewrite vs return usage

   While rewrite can redirect, using 'return 301' is simpler and more reliable for HTTP to HTTPS redirects.

2. Step 2: Identify best practice

   Replacing rewrite with 'return 301 https://$host$request_uri;' fixes the redirect issue.

3. Final Answer:

   The rewrite directive should be replaced with 'return 301 https://$host$request_uri;' -> Option A

4. Quick Check:

   Use 'return 301' for clean HTTP to HTTPS redirect [OK]

Hint: Use 'return 301' instead of rewrite for HTTPS redirect [OK]

Common Mistakes:

• Thinking missing semicolon causes failure
• Changing listen port to 443 for HTTP redirect
• Assuming server_name is the problem

5. You want to redirect HTTP to HTTPS but only for the domain secure.example.com, leaving other domains on HTTP. Which nginx config snippet achieves this?

hard

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

B. server { listen 80 default_server; return 301 https://$host$request_uri; }

C. server { listen 443 ssl; server_name secure.example.com; return 301 http://$host$request_uri; }

D. server { listen 80; server_name _; return 301 https://$host$request_uri; }

Solution

1. Step 1: Match only the desired domain

   Using 'server_name secure.example.com;' limits redirect to that domain only.

2. Step 2: Redirect HTTP on port 80 to HTTPS

   Listening on port 80 and returning 301 redirect to HTTPS URL ensures only that domain redirects.

3. Final Answer:

   server { listen 80; server_name secure.example.com; return 301 https://$host$request_uri; } -> Option A

4. Quick Check:

   Specific server_name + return 301 = domain-only redirect [OK]

Hint: Use server_name to limit redirect to one domain [OK]

Common Mistakes:

• Using default_server redirects all domains
• Redirecting on port 443 instead of 80
• Using wildcard server_name '_' incorrectly