Include directive for modular config in Nginx - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the effect of this nginx config snippet?

Given this nginx configuration snippet, what will be the result when nginx starts?

http {
    include /etc/nginx/conf.d/*.conf;
}

Nginx

http {
    include /etc/nginx/conf.d/*.conf;
}

A nginx loads only the first .conf file found in /etc/nginx/conf.d/

B nginx ignores the include directive because wildcards are not supported

C nginx throws a syntax error due to invalid include path

D nginx loads all configuration files ending with .conf from /etc/nginx/conf.d/ directory

💡 Hint

The include directive supports wildcards to modularize configs.

The include directive in nginx supports wildcards like *.conf to load multiple configuration files from a directory, allowing modular configuration.

❓ Configuration

intermediate

Choose the correct syntax to include a single config file

Which option correctly includes the file /etc/nginx/sites-enabled/example.conf inside the server block?

Nginx

server {
    # include directive here
}

A include /etc/nginx/sites-enabled/example.conf;

B include "/etc/nginx/sites-enabled/example.conf"

C include /etc/nginx/sites-enabled/example.conf

D include '/etc/nginx/sites-enabled/example.conf';

💡 Hint

Include directive requires a semicolon at the end.

The include directive syntax requires the path followed by a semicolon. Quotes are optional but not required.

❓ Troubleshoot

advanced

Why does nginx fail to start with this include?

You added this line to your nginx.conf:

include /etc/nginx/conf.d/*.conf;

But nginx fails to start with an error:
nginx: [emerg] open() "/etc/nginx/conf.d/invalid.conf" failed (2: No such file or directory)
What is the most likely cause?

Nginx

include /etc/nginx/conf.d/*.conf;

A The include directive does not support wildcards in nginx

B One of the files matched by the wildcard does not exist or has been deleted

C The directory /etc/nginx/conf.d/ does not have read permissions

D nginx.conf syntax error unrelated to include

💡 Hint

Check if all files matched by the wildcard exist.

If any file matched by the wildcard does not exist or is a broken symlink, nginx will fail to start with an open() error.

🔀 Workflow

advanced

Order the steps to modularize nginx config using include

Put these steps in the correct order to modularize nginx configuration using the include directive:

A 1,3,2,4

B 2,1,3,4

C 3,1,2,4

D 1,2,3,4

💡 Hint

Think about creating directory before placing files and including them.

First create the directory, then place config files inside, then add include directive, finally test and reload nginx.

✅ Best Practice

expert

Which practice is best for modular nginx config using include?

Which option is the best practice for organizing nginx configuration files using the include directive?

A Use include directive only for SSL certificates paths

B Put all configuration in a single large nginx.conf file without includes

C Use include with wildcards to load multiple small config files grouped by function or site

D Avoid using include directive to prevent complexity

💡 Hint

Modular config helps maintainability and clarity.

Using include with wildcards to load multiple small config files grouped logically is best practice for maintainability and clarity.

Practice

1. What is the main purpose of the include directive in nginx configuration?

easy

A. To define a new server block

B. To start the nginx server

C. To insert the contents of another configuration file into the current file

D. To reload the nginx configuration without downtime

Solution

1. Step 1: Understand the role of include directive

   The include directive is used to insert the contents of one file into another configuration file.

2. Step 2: Compare with other options

   Starting the server, defining server blocks, or reloading configs are done by other commands or directives, not include.

3. Final Answer:

   To insert the contents of another configuration file into the current file -> Option C

4. Quick Check:

   Include directive = insert config file [OK]

Hint: Include means 'add file content here' in config [OK]

Common Mistakes:

• Confusing include with server start commands
• Thinking include defines servers or reloads configs
• Assuming include runs commands instead of inserting files

2. Which of the following is the correct syntax to include all configuration files ending with .conf from the /etc/nginx/conf.d/ directory?

easy

A. include /etc/nginx/conf.d/*.conf;

B. include /etc/nginx/conf.d/*.conf

C. include /etc/nginx/conf.d/*.conf();

D. include /etc/nginx/conf.d/*.conf{};

Solution

1. Step 1: Recall nginx include syntax

   The correct syntax requires the path with wildcard and ends with a semicolon: include path/*.conf;.

2. Step 2: Compare options to correct syntax

   The valid syntax is include /etc/nginx/conf.d/*.conf;. Syntax with parentheses, missing semicolon, or extra braces causes parsing errors.

3. Final Answer:

   include /etc/nginx/conf.d/*.conf; -> Option A

4. Quick Check:

   Include syntax ends with semicolon [OK]

Hint: Include paths always end with a semicolon in nginx [OK]

Common Mistakes:

• Omitting the semicolon at the end
• Adding parentheses or braces incorrectly
• Using wrong wildcard syntax

3. Given this nginx config snippet:

http {
    include /etc/nginx/mime.types;
    include /etc/nginx/conf.d/*.conf;
}

What happens when nginx loads this configuration?

medium

A. It inserts the contents of mime.types and all .conf files from conf.d into the http block

B. It ignores the include directives because they are inside http

C. It only loads mime.types but not the files in conf.d

D. It throws a syntax error because multiple includes are not allowed

Solution

1. Step 1: Understand include behavior inside blocks

   Include inserts file contents exactly where placed, even inside blocks like http.

2. Step 2: Analyze the given includes

   Both mime.types and all .conf files in conf.d are included inside http, so their contents become part of http.

3. Final Answer:

   It inserts the contents of mime.types and all .conf files from conf.d into the http block -> Option A

4. Quick Check:

   Include inserts files where placed [OK]

Hint: Include works anywhere in config blocks [OK]

Common Mistakes:

• Thinking include only works at top level
• Assuming include causes syntax errors with multiple files
• Believing include ignores wildcards inside blocks

4. You wrote this in your nginx config:

include /etc/nginx/conf.d/*.conf

But nginx fails to start with a syntax error. What is the most likely cause?

medium

A. The wildcard *.conf is not supported in include

B. Missing semicolon at the end of the include directive

C. The path must be relative, not absolute

D. Include directive cannot be used inside http block

Solution

1. Step 1: Check syntax rules for include

   Every nginx directive must end with a semicolon; missing it causes syntax errors.

2. Step 2: Validate other options

   Wildcards are supported, absolute paths are allowed, and include works inside http.

3. Final Answer:

   Missing semicolon at the end of the include directive -> Option B

4. Quick Check:

   Every directive ends with semicolon [OK]

Hint: Always end include lines with semicolon [OK]

Common Mistakes:

• Forgetting the semicolon at line end
• Thinking wildcards are invalid
• Assuming include only works outside blocks

5. You want to organize your nginx config by splitting server blocks into separate files inside /etc/nginx/sites-enabled/. Which is the best way to include all these files in your main nginx.conf?

hard

A. Add include /etc/nginx/sites-enabled/*.conf; inside the server block

B. Add include /etc/nginx/sites-enabled/*.conf; outside any block at the top of nginx.conf

C. Add include /etc/nginx/sites-enabled/*.conf; inside the events block

D. Add include /etc/nginx/sites-enabled/*.conf; inside the http block

Solution

1. Step 1: Understand where server blocks belong

   Server blocks must be inside the http block in nginx configuration.

2. Step 2: Determine correct include placement

   Including all server config files inside http ensures they are loaded properly. Including outside blocks or inside events or server blocks is invalid.

3. Final Answer:

   Add include /etc/nginx/sites-enabled/*.conf; inside the http block -> Option D

4. Quick Check:

   Server blocks go inside http block [OK]

Hint: Include server configs inside http block [OK]

Common Mistakes:

• Placing include outside http block
• Including inside events block
• Trying to include inside a server block