Nginx vs Apache comparison - Practice Questions

Challenge - 5 Problems

🧠 Conceptual

intermediate

Key difference in handling connections

Which statement correctly describes how Nginx and Apache handle client connections?

A Both Nginx and Apache use process-driven, synchronous architectures.

B Both Nginx and Apache use event-driven, asynchronous architectures.

C Nginx uses an event-driven, asynchronous architecture, while Apache uses a process-driven, synchronous model.

D Apache uses an event-driven, asynchronous architecture, while Nginx uses a process-driven, synchronous model.

💡 Hint

Think about how each server manages multiple requests at the same time.

Nginx uses an event-driven model that handles many connections efficiently with fewer resources. Apache traditionally uses a process or thread per connection, which can be less efficient under heavy load.

💻 Command Output

intermediate

Check active worker processes

What is the output of the following command on a server running Nginx?

ps aux | grep nginx | grep -v grep

A Shows only one Nginx process running.

B Shows multiple Nginx worker processes and one master process running.

C Returns a syntax error due to incorrect command.

D Shows no output because Nginx is not running.

💡 Hint

Consider how Nginx manages its processes.

Nginx runs one master process and multiple worker processes to handle requests. The command lists all these processes except the grep command itself.

❓ Configuration

advanced

Load balancing configuration in Nginx

Which Nginx configuration snippet correctly sets up a simple round-robin load balancer for two backend servers?

A

upstream backend {
    server backend1.example.com weight=2;
    server backend2.example.com weight=3;
}

server {
    location / {
        proxy_pass http://backend;
    }
}

B

server {
    proxy_pass backend1.example.com backend2.example.com;
}

C

upstream backend {
    server backend1.example.com;
    server backend2.example.com;
    load_balance round_robin;
}

server {
    location / {
        proxy_pass http://backend;
    }
}

D

upstream backend {
    server backend1.example.com;
    server backend2.example.com;
}

server {
    location / {
        proxy_pass http://backend;
    }
}

💡 Hint

Look for the standard way to define upstream servers and proxy pass.

Option D correctly defines an upstream block with two servers and proxies requests to it. Option D adds weights which is valid but changes load balancing behavior. Option D and D have syntax errors or invalid directives.

❓ Troubleshoot

advanced

Diagnosing 502 Bad Gateway error

You have Nginx configured as a reverse proxy to an application server. When accessing the site, you get a 502 Bad Gateway error. Which is the most likely cause?

A The backend application server is not running or unreachable.

B Nginx configuration file syntax error.

C Nginx is running on a different port than the backend server.

D The client browser cache is corrupted.

💡 Hint

502 means Nginx cannot get a valid response from the backend.

A 502 Bad Gateway error usually means Nginx tried to connect to the backend server but failed because it is down or unreachable. Configuration syntax errors cause startup failures, not 502 errors. Port mismatch is a cause but is covered by unreachable backend. Browser cache does not cause 502.

✅ Best Practice

expert

Optimizing static content delivery

Which Nginx configuration snippet best improves performance by efficiently serving static files?

A

location /static/ {
    root /var/www/html;
    expires 30d;
    add_header Cache-Control "public";
    try_files $uri =404;
}

B

location /static/ {
    proxy_pass http://backend;
    expires 30d;
}

C

location /static/ {
    root /var/www/html;
    proxy_cache off;
}

D

location /static/ {
    root /var/www/html;
    deny all;
}

💡 Hint

Think about caching headers and direct file serving.

Option A sets caching headers and serves files directly from disk, improving performance. Option A proxies static files to backend, which is inefficient. Option A disables caching. Option A denies access to static files.