🔴 1) 502 Bad Gateway — How to Fix It (Nginx + PHP-FPM)

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🔴 1) 502 Bad Gateway — How to Fix It (Nginx + PHP-FPM)

✅ Featured Snippet Answer

502 Bad Gateway happens when Nginx can’t communicate with PHP-FPM.
Fix it by restarting PHP-FPM, matching PHP versions, checking socket paths, increasing timeouts, and ensuring PHP-FPM is running.

—

🔍 Common Causes

PHP-FPM service stopped or crashed
PHP version mismatch (Nginx → PHP socket)
Incorrect fastcgi_pass path
Low memory / no swap on VPS
PHP scripts timing out

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🛠️ Step-by-Step Fix

Step 1 — Restart PHP-FPM (FIRST)

$$
service php-fpm restart

or

service php8.2-fpm restart
$$

Step 2 — Check PHP-FPM status

$$
systemctl status php8.2-fpm
$$

If it’s inactive or failed, that’s your problem.

—

Step 3 — Match Nginx socket to PHP version

Check PHP socket:

$$
ls /run/php/
$$

Example correct config:

$$
fastcgi_pass unix:/run/php/php8.2-fpm.sock;
$$

Mismatch = 502.

—

Step 4 — Increase PHP timeout (heavy scripts)

Edit php.ini:

$$
max_execution_time = 120
memory_limit = 512M
$$

Restart PHP-FPM again.

—

Step 5 — Add swap (1GB VPS FIX)

$$
fallocate -l 1G /swapfile
chmod 600 /swapfile
mkswap /swapfile
swapon /swapfile
$$

—

📌 Summary

Error: 502 Bad Gateway
Cause: PHP-FPM not responding
Fix: Restart PHP-FPM, fix socket, add swap

Category: Technology & Computing → Web Development
Hashtags:
#502error #nginx #phpfpm #vps #serveradmin

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🔒 2) 403 Forbidden — Permissions Explained (Linux, Nginx, Apache)

✅ Featured Snippet Answer

403 Forbidden means the server refuses access due to permissions or rules.
Fix it by correcting file permissions, ownership, web server rules, and security modules.

—

🔍 Common Causes

Wrong file/folder permissions
Wrong ownership (root instead of web user)
Missing index.php or index.html
.htaccess or Nginx deny rules
SELinux / security modules

—

🛠️ Correct Permissions (SAFE DEFAULT)

Folders

$$
find /site/path -type d -exec chmod 755 {} \;
$$

Files

$$
find /site/path -type f -exec chmod 644 {} \;
$$

—

Correct Ownership (VERY IMPORTANT)

$$
chown -R www-data:www-data /site/path
$$

(or nginx:nginx depending on server)

—

🧪 Quick Test

If this fixes it instantly → permissions were the issue.

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📌 Summary

Error: 403 Forbidden
Cause: Permission / access rule issue
Fix: chmod + chown + server config

Category: Technology & Computing → Web Development
Hashtags:
#403error #permissions #linux #webserver #hosting

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🔐 3) ERR_SSL_VERSION_OR_CIPHER_MISMATCH — Fix SSL Properly

✅ Featured Snippet Answer

ERR_SSL_VERSION_OR_CIPHER_MISMATCH occurs when the browser and server don’t share compatible SSL/TLS settings.
Fix it by updating SSL certificates, enabling modern TLS versions, and disabling outdated ciphers.

—

🔍 Common Causes

Old SSL certificate
TLS 1.0 / 1.1 only enabled
Invalid cipher suite
Cloudflare SSL mismatch
Outdated OpenSSL

—

🛠️ Step-by-Step Fix

Step 1 — Renew SSL certificate

If using Let’s Encrypt:

$$
certbot renew
$$

—

Step 2 — Enable modern TLS (Nginx)

$$
ssl_protocols TLSv1.2 TLSv1.3;
ssl_ciphers HIGH:!aNULL:!MD5;
$$

Reload Nginx:

$$
nginx -s reload
$$

—

Step 3 — Cloudflare users

Set:

$$
SSL Mode: Full (strict)
$$

❌ Do not use Flexible SSL.

—

📌 Summary

Error: SSL version/cipher mismatch
Cause: Outdated TLS or certificate
Fix: TLS 1.2+, renew cert

Category: Internet, Apps & Social Media → Websites & Platforms
Hashtags:
#ssl #tls #cloudflare #https #security

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This is your traffic magnet + internal linking engine.

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📌 Website Errors & Fixes — Start Here

If your website is down, broken, or showing strange errors, this hub links to clear, step-by-step solutions.

🔌 DNS Errors

👉 DNS_PROBE_STARTED — What It Means & How to Fix It (2026)
https://1337x.co.za/d/26-my-website-shows-dns-probe-started-what-it-means-how-to-fix-it-2026
👉 DNS_PROBE_FINISHED_NXDOMAIN — Fix Guide
(add link)

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🔐 SSL & Security Errors

👉 ERR_SSL_VERSION_OR_CIPHER_MISMATCH — Fix SSL Issues
👉 Your Connection Is Not Private — Certificate Fix

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🔁 Redirect & Access Errors

👉 ERR_TOO_MANY_REDIRECTS — Redirect Loop Fix
👉 403 Forbidden — Permissions Explained

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⚙️ Server & Backend Errors

👉 502 Bad Gateway — Nginx + PHP-FPM Fix
👉 503 Service Unavailable — Server Overload Fix
👉 504 Gateway Timeout — Slow Backend Fix

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🧰 PHP & Composer Errors

👉 Composer Error: Call to Undefined Function putenv()
👉 PHP Fatal Error: Declaration Must Be Compatible
👉 Composer Memory Exhausted — Fix

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👉 Pin this globally.

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🚀 What You Should Do Next (VERY IMPORTANT)

Publish all individual error posts
Publish the Website Errors Hub
Add internal links both ways
Pin the hub
Keep adding new errors under it