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Why Am I Seeing Error Code?

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The phenomenon of receiving Error Code 525, or “SSL Handshake Failed,” leaves most users as puzzled as it does not allow them to enter the site. This type of error arises mainly as a result of Cloudflare; a popular content delivery network (CDN), not being able to authenticate with your server. To determine how to fix the problem behind Error Code 525, it is helpful to know the causes of the problem to regain accessibility of websites. 

To help you get a better understanding why you are experiencing this error let me present to you the four typical causes for this error.

  1. The expired or invalid SSL/TLS certificates.

Over fifty percent of instances of Error 525 could be contributed to having an expired or invalid SSL/TLS certificate on your origin server. I was able to verify that SSL certificates guarantee secure communication but when they have expired or maybe misconfigured do not allow the handshake process to progress. To solve this problem, you should first of all verify the status of your SSL certificate then if it is expired, renew it. Another thing that is critical to getting a successful connection is checking to make sure the certificate was installed correctly and is associated with your domain.

2.SSL Settings Don’t Match:

Cloudflare has three types of SSL modes known as Flexible, Full, and Full (Strict). Another cause of Error 525 is a discrepancy between the SSL used by your server and the SSL setting on Cloudflare. For instance, if you choose Full (Strict) in Cloudflare settings then it means Cloudflare and your origin server must have a valid SSL certificate. When the settings do not align, Cloudflare will not be able to connect securely. It is good to check on your SSL setting configuration in Cloudflare if it is the same as the one on your server.

  1. SSL/TLS Protocol Versions Not Supported on the Server

Cloud flare expects the newest version of SSL/TLS protocols to make a connection secure. If your server has active TLS 1.0 or 1.1 protocols, you are likely to meet a connection issue with Cloudflare. For avoiding Error 525 allow the newer versions such as TLS 1.2 or TLS 1.3 on the server. Both the security and compatibility aspects are improved, such that handshake errors with Cloudflare are less likely to interfere.

  1. Closed ports or firewall limit.

Cloudflare communicates with origin servers through some port number, for instance, port number 443 for HTTPS. If these ports are blocked or restricted by your server’s firewall, Cloudflare can’t establish the SSL connection and we get the Error 525. To prevent this, be sure your firewall permits traffic on TCP port 443 and on any other port that needs to be opened. Checking the firewall and the security option consistently allows your servers to open for secure connections.

 Conclusion 

In conclusion, if you’ve come across Error Code 525, it means that Cloudflare cannot establish a secure connection with your server; however, understanding what causes such a problem can help. In future to avoid Error Code 525, one ought to perform regular checks of valid SSL certificates, has correct SSL settings, update SSL/TLS protocols to acknowledged compatible ones, set right firewall rules and manage server load frequently. With these knowledge, you will be able to keep your connection between Cloudflare and your site safe and efficient for the end users.