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Error 520: Troubleshooting and Fixing Cloudflare Issue

In this article, I will discuss troubleshooting and fixing Error 520, a common issue that can occur with Cloudflare.

Understanding the Causes of Error 520

Error 520 is a common issue that can occur due to various reasons. One of the main causes of Error 520 is a problem with the origin server. Check if your server is working properly and is not overloaded. Another possible cause is a misconfiguration in your Cloudflare settings. Make sure your settings are correctly configured to avoid this error. Additionally, Error 520 can also be caused by issues with your firewall or proxy server.

Check these settings to ensure they are not blocking necessary connections.

Initial Steps for Troubleshooting Error 520

1. Check Cloudflare Status: Ensure that Cloudflare is not experiencing any downtime or issues by visiting their status page.

2. Clear Browser Cache: Clear your browser’s cache and cookies to eliminate any stored data that could be causing the error.

3. Check Firewall Settings: Review your firewall settings to ensure that Cloudflare is not being blocked.

4. Disable Proxy Servers: Temporarily disable any proxy servers to see if they are causing the issue.

5. Review .htaccess File: Check your .htaccess file for any misconfigurations that could be affecting Cloudflare.

6. Contact Web Host: Reach out to your web hosting provider to see if the issue is related to server settings.

Pausing Cloudflare for Diagnosis

To pause Cloudflare for diagnosis, log in to your Cloudflare account and navigate to the Overview tab of your website. Click on the orange cloud icon next to your domain name to toggle it to gray. This will temporarily disable Cloudflare services, allowing you to troubleshoot the Error 520 issue without interference. Remember to re-enable Cloudflare once you have identified and fixed the problem. Pausing Cloudflare can help pinpoint whether the issue lies with Cloudflare or your origin server, aiding in a more targeted resolution.

By pausing Cloudflare, you can isolate the source of the Error 520 and focus on resolving it efficiently. Keep in mind that pausing Cloudflare may make your website vulnerable to attacks, so only do so for diagnostic purposes. Once you have identified the root cause of the issue, you can take appropriate steps to prevent it from recurring in the future.

Checking and Correcting DNS Records

To check and correct DNS records, access your domain registrar or hosting provider’s dashboard. Look for the DNS management section or a similar option. Locate the DNS records for your domain, including the A, CNAME, MX, and TXT records. Review each record for accuracy and make any necessary corrections. Ensure that the records point to the correct IP addresses or domains.

After making changes, it may take some time for the updates to propagate across the internet. To expedite this process, you can clear the DNS cache on your local machine or use an online tool to check the DNS propagation status. Monitor the changes to ensure they have been applied correctly and have resolved the Error 520 issue.

Restarting PHP to Resolve Issues

To resolve Error 520 on Cloudflare, restarting PHP may be necessary. First, access your hosting control panel or server dashboard. Locate the option to restart PHP services. This may vary depending on your hosting provider or server setup.

Once you have restarted PHP, clear your browser cache and refresh the webpage to see if the issue persists. If the error continues, you may need to investigate further or contact your hosting provider for assistance.

Analyzing Headers and Cookies

Analyzing Headers and Cookies: When troubleshooting Error 520 with Cloudflare, it’s essential to analyze headers and cookies. Check for any inconsistencies or errors in the headers to pinpoint the issue. Make sure cookies are correctly set and not causing conflicts. Inspect the headers for any missing or incorrect information that could be triggering the error. Pay attention to the cookies being transmitted and their values.

Headers and cookies play a crucial role in the communication between the client and server, so thorough analysis is key to resolving the Cloudflare issue efficiently.

Disabling .htaccess File

To disable the .htaccess file and troubleshoot Cloudflare Error 520, follow these steps:

1. Access your website’s root directory using a file manager or FTP client.

2. Locate the .htaccess file in the root directory.

3. Rename the .htaccess file to something else, like .htaccess_backup.

4. Refresh your website and check if the Cloudflare Error 520 is resolved.

Disabling the .htaccess file temporarily can help identify if it is causing the Cloudflare issue.

Investigating Web Server Error Logs

Analyzing the error logs can also provide valuable insight into any server-side configurations that may be impacting the Cloudflare connection. Look for any configurations that could be conflicting with Cloudflare’s settings or causing issues with the connection. Make sure to review any recent changes or updates that may have been made to the server settings, as these could be contributing to the Error 520.

In some cases, the error logs may reveal that the server is unable to establish a connection with Cloudflare due to a firewall or proxy server blocking the request. Check for any firewall rules or proxy configurations that could be interfering with the connection and adjust them accordingly to allow the Cloudflare connection to go through. By carefully reviewing the web server error logs, you can effectively troubleshoot and fix Cloudflare Error 520.

Using cURL Commands for Advanced Troubleshooting

To troubleshoot and fix a Cloudflare Error 520, you can use cURL commands for advanced troubleshooting. To start, run the following command in your terminal:

curl -v

This will provide you with detailed information about the HTTP request and response. Look for any errors or clues in the output that can help you pinpoint the issue.

If you suspect a firewall or network issue, try using cURL with the –resolve flag to bypass DNS resolution:

curl -v –resolve ‘’

This command will send the request directly to the IP address you specify.

Additionally, you can use cURL to test different headers or cookies that may be causing the Error 520. Make sure to check the cURL documentation for more advanced options and troubleshooting techniques.

Contacting Cloudflare Support for Help

If you are experiencing Error 520 on Cloudflare and need help, you can contact Cloudflare Support for assistance. To do this, log in to your Cloudflare account and navigate to the Support section. Here, you can submit a ticket detailing the issue you are facing. Be sure to include relevant information such as your domain name, any error messages you are receiving, and steps you have already taken to troubleshoot the problem.

Cloudflare’s support team will work to diagnose and resolve the issue as quickly as possible. Keep an eye on your email for updates from Cloudflare Support regarding the progress of your ticket. If necessary, they may request additional information or steps to help resolve the Error 520.

Generating and Interpreting HAR Files

Once the HAR file is generated, carefully examine the data for any anomalies or error messages. Look for long loading times, failed requests, or unusual responses that could indicate the source of the problem. Pay special attention to headers, cookies, and response codes within the HAR file.

By analyzing and interpreting the HAR file, you can pinpoint the issue causing Error 520 and take appropriate steps to resolve it effectively.

Resolving Common Reasons Behind Error 520

  • Check Cloudflare Status
    • Visit Cloudflare’s status page to see if there are any ongoing issues
    • If there are no reported issues, move on to the next step
  • Check Origin Server
    • Make sure your origin server is properly configured and running
    • Check for any server-side issues that could be causing the error
  • Review Firewall and Security Settings
    • Ensure that your firewall settings are not blocking Cloudflare’s requests
    • Review any security settings that could be causing the error
  • Clear Browser Cache
    • Clear your browser’s cache and cookies to eliminate any stored data causing the error
    • Refresh the page to see if the error has been resolved

Adjusting Cloudflare Settings for Resolution

To adjust Cloudflare settings for resolution of Error 520, start by logging into your Cloudflare account and navigating to the “Firewall” section. Next, adjust the security level to a lower setting to see if that resolves the issue. If not, try whitelisting your server’s IP address in the Cloudflare dashboard. Additionally, you can check your server logs for any clues as to what might be causing the error. Finally, ensure that your origin server is properly configured to work with Cloudflare by checking the DNS settings.

Preventative Measures for Error 520

To prevent Error 520 in Cloudflare, check your server logs for any underlying issues causing the error. Ensure your server is properly configured to handle the traffic load and requests. Check your firewall settings to make sure they are not blocking any necessary connections. Clear your browser cache and cookies to eliminate any potential conflicts. Update your DNS records to ensure they are pointing to the correct IP address. Consider reaching out to Cloudflare support for further assistance if the issue persists.


How do I fix error code 520?

To fix error code 520, you can try restarting PHP/Apache/Nginx, whitelisting Cloudflare IPs, adjusting TCP idle timeouts, reducing header size, emptying response header, temporarily disabling Cloudflare, activating development mode, and checking your server’s error logs.

What is error 520 on DDOS?

Error 520 on DDOS is a response from Cloudflare indicating that a web server cannot fulfill a request due to receiving an invalid or incorrectly interpreted request, resulting in an empty response.

How to fix Cloudflare error 502?

To fix Cloudflare error 502, you can wait a few minutes and reload the page. If the error persists, try clearing your browser cache and reloading the page.

How to fix host error Cloudflare?

To fix host error Cloudflare, you should start by confirming that your Cloudflare DNS records are accurate. Additionally, check headers and cookies, investigate error logs, and use a cURL command to troubleshoot. If necessary, consider disabling Cloudflare or contact their support for further assistance.

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