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503

Service Unavailable

The server is currently unable to handle the request due to maintenance or overloading.

Common Causes

  • Server maintenance
  • Server overloaded
  • Resource exhaustion
  • Rate limiting
  • Deployment in progress

Fix Solutions

Scale resources

Add more server capacity or optimize resource usage.

Check maintenance status

Verify if scheduled maintenance is in progress.

Code Examples

# Maintenance mode
server {
    listen 80;
    return 503;
    error_page 503 @maintenance;
    location @maintenance {
        root /var/www/html;
        rewrite ^(.*)$ /maintenance.html break;
    }
}

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