Troubleshooting Common SSL/TLS Issues

Common SSL/TLS problems and their solutions:

Mixed Content Warnings: Ensure all resources load over HTTPS:

# Apache: Force HTTPS for all resources
Header always set Content-Security-Policy "upgrade-insecure-requests"

# Nginx: Force HTTPS for all resources
add_header Content-Security-Policy "upgrade-insecure-requests" always;

Certificate Chain Issues: Ensure complete certificate chain:

# Verify certificate chain order
cat cert.pem intermediate.pem root.pem > fullchain.pem

# Test chain completeness
openssl verify -CAfile root.pem -untrusted intermediate.pem cert.pem

Cipher Suite Compatibility: Balance security with client compatibility:

# Nginx compatibility mode for older clients
ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3;
ssl_ciphers 'ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA:ECDHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-RSA-AES256-SHA256:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:AES128-SHA:AES256-SHA:!DSS';