Prerequisites:

1. PRTG Installation: Ensure PRTG Network Monitor is installed and running in your environment.
2. Access to SSL/TLS-enabled Services: You need access to SSL/TLS-enabled services, such as web servers, mail servers, or applications, for monitoring purposes.
3. Administrator Access: Obtain administrative access to configure sensors and settings in PRTG.

Setting Up SSL/TLS Handshake Monitoring:

1. Add SSL/TLS-enabled Device(s): In PRTG, navigate to "Devices" and add the SSL/TLS-enabled device(s) you want to monitor.
2. Install SSL/TLS Sensor(s): Click on the device you added, then go to "Add Sensor" > "By Type" > Select "SSL Security Check Sensor."
3. Configure Sensor Parameters: Define the parameters for monitoring, including the target SSL/TLS service endpoint (e.g., hostname, IP address, port number).
4. Select Monitoring Parameters: Choose the monitoring parameters you want to track, such as SSL/TLS handshake failures, certificate validation errors, cipher suite support, and protocol versions.
5. Test Configuration: Verify that the sensor can successfully perform SSL/TLS handshake checks and retrieve relevant security information from the target service endpoint.

Monitoring SSL/TLS Handshake Failures and Errors:

1. Real-time Monitoring: Access the PRTG dashboard to view real-time updates on SSL/TLS handshake failures and errors.
2. Handshake Failures: Monitor SSL/TLS handshake failures to detect issues with cryptographic negotiation, authentication, or protocol compatibility between clients and servers.
3. Certificate Validation Errors: Track certificate validation errors to identify potential issues with SSL/TLS certificates, such as expired certificates, invalid certificate chains, or untrusted certificate authorities.
4. Cipher Suite Support: Monitor cipher suite support to ensure that SSL/TLS-enabled services support secure cryptographic algorithms and mitigate the risk of vulnerabilities, such as outdated or weak cipher suites.
5. Protocol Versions: Monitor SSL/TLS protocol versions to enforce compliance with security best practices and regulatory requirements, such as disabling deprecated or insecure protocols (e.g., SSLv2, SSLv3).

Best Practices:

1. Certificate Management: Implement a comprehensive SSL/TLS certificate management process, including regular certificate expiration checks, certificate renewal procedures, and certificate revocation handling.
2. Protocol Hardening: Configure SSL/TLS-enabled services to use the latest recommended protocol versions (e.g., TLS 1.2 or higher) and disable deprecated or insecure protocols (e.g., SSLv2, SSLv3) to mitigate security risks.
3. Cipher Suite Configuration: Configure SSL/TLS cipher suites to prioritize strong cryptographic algorithms and key exchange mechanisms while minimizing the risk of vulnerabilities, such as BEAST, POODLE, or FREAK attacks.
4. Secure Communication: Ensure that SSL/TLS-enabled services enforce secure communication practices, such as mutual authentication, perfect forward secrecy (PFS), and secure renegotiation, to enhance security and protect against unauthorized access or data interception.
5. Security Compliance: Monitor SSL/TLS handshake failures and errors to assess compliance with security standards, such as PCI DSS, HIPAA, or GDPR, and address any non-compliant configurations or vulnerabilities promptly.

Troubleshooting:

1. Connection Issues: Ensure that PRTG can establish SSL/TLS connections to the target service endpoints and retrieve handshake data successfully.
2. Sensor Configuration: Double-check sensor settings, including target endpoint details and monitoring parameters, and verify that the correct sensor type is used for SSL/TLS handshake monitoring.
3. Certificate Validation: Investigate certificate validation errors to identify the root cause, such as expired certificates, certificate chain issues, or certificate authority trust problems, and take appropriate remediation actions.
4. Protocol Compatibility: Troubleshoot SSL/TLS handshake failures related to protocol compatibility issues by verifying protocol versions supported by both clients and servers and adjusting configuration settings accordingly.
5. Cipher Suite Negotiation: Analyze SSL/TLS handshake failures related to cipher suite negotiation problems, such as incompatible algorithms or key lengths, and update cipher suite configurations to ensure compatibility and security.

By leveraging PRTG Network Monitor to monitor SSL/TLS handshake failures and errors, you can enhance the security, reliability, and compliance of your network services. Real-time monitoring, proactive alerting, and comprehensive analysis enable you to detect and address SSL/TLS-related issues promptly, minimize security risks, and ensure secure communication between clients and servers. With PRTG, you can effectively manage and optimize SSL/TLS configurations to meet the security requirements and operational needs of your organization.