An SSL handshake failure can disrupt secure connections and impact website functionality. Investigating and resolving SSL handshake issues promptly is crucial for maintaining a secure online environment. This knowledge base provides comprehensive information on how to investigate and address SSL handshake failures in WHM cPanel.

1. Understanding SSL Handshake Failure:

   • An SSL handshake failure occurs when a secure connection cannot be established between a client and a server.

2. Accessing WHM for SSL Handshake Investigation:

   • Log in to WHM using your administrator credentials.

3. Navigating to SSL/TLS Status:

   • Locate and select 'SSL/TLS Status' from the WHM menu.

4. Reviewing Installed SSL Certificates:

   • Check the list of installed SSL certificates to ensure they are valid and properly configured.

5. Identifying Common SSL Handshake Causes:

   • Familiarize yourself with common issues such as certificate expiration, misconfiguration, or compatibility problems.

6. Checking Certificate Expiration Dates:

   • Verify that SSL certificates are not expired, as expired certificates will lead to handshake failures.

7. Reviewing SSL Cipher Suites:

   • Confirm that the server supports secure cipher suites and that they are correctly configured.

8. Inspecting SSL Certificate Chains:

   • Ensure that SSL certificate chains are complete and properly configured to establish trust.

9. Verifying Server Time and Date Settings:

   • Confirm that the server's time and date settings are accurate, as incorrect settings can lead to SSL handshake failures.

10. Reviewing ModSecurity and Firewall Rules:

    • Check ModSecurity and firewall rules to ensure they do not block SSL connections.

11. Examining Server Resource Usage:

    • Monitor server resources such as CPU, memory, and disk usage to ensure they are not overloaded.

12. Inspecting Reverse Proxy Configurations (If Applicable):

    • If using a reverse proxy, verify that it is configured to handle SSL connections properly.

13. Checking SSL Version Compatibility:

    • Ensure that the SSL/TLS versions supported by the server are compatible with the client's capabilities.

14. Utilizing Online SSL Testing Tools (Optional):

    • Use online SSL testing tools to analyze the SSL configuration and identify potential issues.

15. Inspecting Logs for SSL Handshake Errors:

    • Access server logs to identify any specific errors or warnings related to SSL handshakes.

16. Handling Mixed Content Issues (If Applicable):

    • Ensure that all resources on a secure page are loaded via HTTPS to prevent mixed content errors.

17. Educating Users on SSL Best Practices:

    • Provide guidelines to users on SSL certificate management and secure connection practices.

18. Documenting SSL Handshake Investigation Procedures:

    • Keep detailed records of SSL handshake investigation steps taken, including findings and resolutions.

19. Conducting Regular SSL Audits and Certificates Checks:

    • Periodically review SSL configurations and certificates to ensure they remain valid and properly configured.

20. Implementing Security Updates and Patch Management (Optional):

    • Stay up-to-date with security patches and updates to address any known SSL vulnerabilities.

Conclusion:

Effectively investigating and addressing SSL handshake failures in WHM cPanel is crucial for maintaining a secure and reliable web environment. By following the steps outlined in this knowledge base, you can efficiently identify and resolve SSL handshake issues, ensuring secure connections and a seamless user experience. This contributes to an overall more secure and reliable web hosting environment.