The first step in troubleshooting a downed Linux-hosted website is to check server connectivity via ping and SSH; if reachable, inspect the web server (Apache/Nginx) status and logs; next, verify application-level services like PHP-FPM or Node.js processes and their logs; ensure adequate disk space and memory; and finally, confirm firewall and port 80/443 accessibility, testing locally with curl to isolate external blocking issues.

If a website running on a Linux server is down, the first thing to do is stay calm and start systematically checking possible failure points. Don’t jump straight into rebooting everything — that might mask the real issue or even make things worse. Instead, follow a logical flow to identify where the problem lies.

Check Basic Connectivity

Before diving deep, confirm that the server itself is reachable. Sometimes the issue isn’t with the website but with the server being offline or unreachable.

• Try pinging the server:

  ping your_server_ip

  If it doesn’t respond, it could be a network issue or the server might be down.

• Use ssh to try logging in:

  ssh username@your_server_ip

  If you can’t log in, check if the server is powered on or contact your hosting provider.

• If SSH works, move on to deeper checks.

Look at the Web Server (Apache/Nginx)

Most websites on Linux use Apache or Nginx as the web server. If those services are down or misconfigured, the site won’t load.

• Check if the service is running:

  • For Apache:

    systemctl status apache2

  • For Nginx:

    systemctl status nginx

• If it’s not running, try starting it:

  sudo systemctl start apache2
  # or
  sudo systemctl start nginx

• Also, look at the logs for any errors:

  • Apache error log:

    tail -f /var/log/apache2/error.log

  • Nginx error log:

    tail -f /var/log/nginx/error.log

  These logs often show what went wrong — like a syntax error in config files or a missing module.

Check Application-Level Issues

Even if the web server is running fine, the actual application (like WordPress, Node.js app, etc.) might have crashed or thrown an error.

• If it’s a PHP-based site, check PHP-FPM:

  systemctl status php-fpm

• For Node.js apps, see if the process is running:

  ps aux | grep node

  If not, restart it using whatever command was originally used to launch it (e.g., node app.js or via PM2).

• Look at application-specific logs too — they’re usually in /var/log/, inside a folder specific to the app or framework.

Also, make sure there’s enough disk space and memory available:

df -h
free -m

Running out of either can cause a site to go down without obvious service failures.

Verify Firewall and Port Settings

Sometimes the server is up and running fine, but traffic is being blocked by a firewall or security group rule.

• Make sure port 80 (HTTP) and 443 (HTTPS) are open:

  sudo ufw status

  Or, if you're using something like AWS EC2, check the security group settings from the console.

• Test locally if the web server is responding:

  curl http://localhost

  If this returns HTML content, the server is working but something is blocking external access.

Basically, when a website is down, it’s all about narrowing down the problem step by step. Start with connectivity, then move through web server status, application health, and finally firewall or port issues. Most of the time, one of these areas will show the root cause.

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