TLS Handshake Failed: SNI Mismatch Error - How to Fix

TLS Handshake Failed: SNI Mismatch Error - How to Fix

Have you encountered a 'TLS handshake failed | SNI mismatched' error with IP address 45.76.153.249? This error indicates a mismatch between the server certificate and the Server Name Indication (SNI) provided by the client during the TLS handshake process.

Understanding the Problem

The SNI mechanism is vital for websites hosting multiple domains on a single IP address. It allows clients to specify which website they want to connect to, enabling the server to select the appropriate certificate. When there's a mismatch, the server doesn't recognize the requested website and fails to establish a secure connection.

Possible Causes:

• Incorrect SNI Configuration: The server might be configured incorrectly, leading to an SNI mismatch.
• Outdated Certificate: The server's SSL/TLS certificate may be outdated or not compatible with the client's browser.
• Proxy Issues: Proxies or intermediaries between the client and server might interfere with the SNI handshake.
• DNS Errors: Incorrect DNS records might point to the wrong IP address, causing the SNI mismatch.

Troubleshooting and Solutions:

1. Verify Server Configuration: Confirm that the server's SNI settings are correctly configured to match the domain being requested.
2. Update Certificates: Ensure the server's SSL/TLS certificates are up-to-date and valid.
3. Bypass Proxies: Try accessing the website directly without using any proxy servers or VPNs.
4. Clear Browser Cache: Clearing the browser's cache and cookies can sometimes resolve SNI issues.
5. DNS Check: Verify that the domain name resolves correctly to the server's IP address using a DNS lookup tool.

Need Expert Assistance?

If you're unable to resolve the issue, it's recommended to consult a web hosting provider or a security expert for further assistance.