Quick Summary
Error 1016 indicates that the origin server (your web server) is returning an error to Cloudflare. This error prevents Cloudflare from properly serving your website to visitors.
Common Causes
- Origin Server Down or Unreachable: The most common cause is that the web server hosting your website is down, unreachable, or refusing connections. This could be due to server maintenance, unexpected outages, hardware failures, or network issues.
- DNS Resolution Issues: Cloudflare is unable to resolve the DNS records for your origin server. This can happen if the origin DNS records are incorrect, missing, or the DNS server is unresponsive.
- Firewall Blocking Cloudflare: A firewall on your origin server or network could be blocking Cloudflare's IP addresses. Cloudflare needs to be able to connect to your server to retrieve content.
- Incorrect DNS Configuration: The DNS records in your Cloudflare dashboard pointing to your origin server are configured incorrectly (e.g. incorrect IP address).
Step-by-Step Fixes
Method 1: Verify Origin Server Status
Step 1: Check if your origin server is online and responding to requests. You can try accessing your website directly through the origin server's IP address (if known) or via a direct DNS lookup that circumvents Cloudflare.
Step 2: Check your server's resource usage (CPU, memory, disk I/O) to ensure it's not overloaded. High resource usage can cause the server to become unresponsive.
Step 3: Review your server logs (e.g., Apache error logs, Nginx error logs) for specific errors that might indicate the cause of the issue.
Method 2: Check DNS Records
Step 1: Verify that the DNS records in your Cloudflare dashboard are correctly pointing to your origin server's IP address. Double-check for any typos or outdated information.
Step 2: Use a DNS lookup tool (like `dig` or `nslookup`) to check the DNS records associated with your domain. Ensure that the IP address returned matches your origin server's IP address.
Method 3: Allow Cloudflare IPs
Step 1: Ensure that your server's firewall is configured to allow connections from Cloudflare's IP ranges. You can find the latest list of Cloudflare IPs on their official website.
Step 2: If applicable, check any hardware firewalls or network security devices for rules that might be blocking Cloudflare IPs.
Method 4: Pause Cloudflare Temporarily
Step 1: In your Cloudflare dashboard, go to the 'Overview' tab for your domain.
Step 2: Find the 'Quick Actions' section on the right side and click 'Pause Cloudflare on Site'. This will temporarily disable Cloudflare and allow you to access your site directly through your origin server.
Step 3: If your site works correctly after pausing Cloudflare, the issue likely lies within the Cloudflare configuration.
Step 4: After resolving the issue, remember to unpause Cloudflare.