503 Error Troubleshooting

Additionally, a 503 Service Unavailable error was encountered while trying to use an ErrorDocument to handle the request.
after set upwordpress to our demo

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### 🔍 **1. Check Server Resources**
This could happen if:
– The server ran out of **RAM or CPU**.
– Your hosting or local server is under too much load.

✅ **Check this:**
– On local (Docker, DDEV, XAMPP): Check logs or system monitor.
– On hosting (cPanel, EC2): Check server metrics or logs via SSH or hosting panel.

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### 🔧 **2. Check `.maintenance` File**
WordPress creates a `.maintenance` file in the root during updates. If it didn’t get deleted properly:

✅ **Solution:**
– Connect via FTP or file manager.
– Delete `.maintenance` from the WordPress root folder.

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### 🧱 **3. Check `wp-config.php` for Errors**
If you recently edited `wp-config.php`, an error there could trigger a 503.

✅ **Look for:**
– Syntax errors.
– Incorrect database details.

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### 🪵 **4. Check Web Server Logs**
– Apache: `error.log` usually under `/var/log/apache2/`
– Nginx: `error.log` under `/var/log/nginx/`

✅ Look for PHP fatal errors or permission issues.

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### 📄 **5. ErrorDocument Misconfiguration**
The second part of the error says:
> Additionally, a 503 Service Unavailable error was encountered while trying to use an ErrorDocument to handle the request.

This means your `.htaccess` or Apache config has a custom error handler for 503s, and **that handler is broken too**.

✅ Try this:
– Rename `.htaccess` temporarily to see if it fixes the issue.
– Or check if the `ErrorDocument` directive points to a missing file.

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### 🔁 **6. Restart Services**
If you’re using Docker, Apache, or PHP-FPM:

# Docker
docker compose restart

# Apache
sudo systemctl restart apache2

# Nginx
sudo systemctl restart nginx

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### ✅ Final Step: Enable WP_DEBUG
Edit your `wp-config.php` and add:

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);

Then visit the site again. Check the `/wp-content/debug.log` file for the actual cause.

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Let me know if you're using **Docker**, **DDEV**, or shared hosting — I can tailor the fix for your environment.