Basic authentication in Nginx - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the output of this command to create a password file?

You run the command htpasswd -c /etc/nginx/.htpasswd user1 and enter the password pass123. What will be the content format of the file /etc/nginx/.htpasswd?

Nginx

htpasswd -c /etc/nginx/.htpasswd user1

A A file with the username and an encrypted password hash, e.g., user1:$apr1$randomhash

B A JSON file containing username and password fields

C A plain text file with the username and password separated by a colon, e.g., user1:pass123

D An XML file with user credentials inside tags

💡 Hint

The password is not stored in plain text but hashed for security.

The htpasswd command creates a file where the password is stored as a hash, not plain text. This is to keep passwords secure.

❓ Configuration

intermediate

Which nginx configuration snippet correctly enables basic authentication for /admin path?

You want to protect the /admin URL path with basic authentication using the password file at /etc/nginx/.htpasswd. Which configuration snippet will work?

A

location /admin {
  auth_basic "Restricted Area";
  auth_basic_user_file /etc/nginx/.htpasswd;
  allow all;
}

B

location /admin {
  auth_basic "Restricted Area";
  auth_basic_user_file /etc/nginx/passwd;
}

C

location /admin {
  auth_basic "Restricted Area";
  auth_basic_user_file /etc/nginx/.htpasswd;
}

D

location /admin {
  auth_basic_user_file /etc/nginx/.htpasswd;
  auth_basic off;
}

💡 Hint

Check that auth_basic is enabled and the correct file path is used.

Option C correctly enables basic authentication with a realm name and points to the correct password file. Option C disables auth_basic. Option C uses a wrong file path. Option C includes an unnecessary 'allow all;' directive.

❓ Troubleshoot

advanced

Why does nginx ignore basic authentication despite correct config?

You configured nginx with basic authentication for /secure path, but users can access it without a password prompt. What is the most likely cause?

A The auth_basic directive is inside a location block but the location is overridden by another location without auth_basic.

B The password file /etc/nginx/.htpasswd is empty.

C The nginx service was restarted after configuration changes.

D The client browser does not support basic authentication.

💡 Hint

Check if another location block matches the request without authentication.

If another location block matches the request and does not have auth_basic enabled, nginx will serve that block without authentication, ignoring the intended protection.

🔀 Workflow

advanced

What is the correct workflow to enable basic authentication on nginx?

Arrange the steps in the correct order to enable basic authentication on nginx for a website.

A 2,1,3,4

B 1,2,3,4

C 1,3,2,4

D 2,3,1,4

💡 Hint

Think about creating credentials before telling nginx to use them.

You first create the password file, then configure nginx to use it, reload nginx to apply, and finally test the setup.

✅ Best Practice

expert

Which practice improves security when using basic authentication with nginx?

Basic authentication sends credentials encoded but not encrypted. Which practice best improves security when using it?

A Disable logging in nginx to avoid recording authentication attempts.

B Use longer usernames and passwords in the htpasswd file.

C Store the password file in the web root directory for easy access.

D Use HTTPS (TLS) to encrypt the connection so credentials are protected in transit.

💡 Hint

Think about protecting data sent over the network.

Basic authentication credentials are only base64 encoded, not encrypted. Using HTTPS encrypts the entire connection, protecting credentials from being intercepted.