config
SSL/TLS cipher or protocol version mismatch
ERR_SSL_VERSION_OR_CIPHER_MISMATCH|no shared cipher|handshake failure
Fixes
- 1.Update cipher suite to include modern ciphers: ssl_ciphers 'ECDHE-ECDSA-AES128-GCM-SHA256:...'
- 2.Enable TLS 1.2 and 1.3: ssl_protocols TLSv1.2 TLSv1.3 (disable SSLv3, TLS 1.0, TLS 1.1)
- 3.Check if client supports any of the server's offered ciphers — update one or both sides
sslcipherprotocol
Related Errors
config3 fixes
Nginx 502 Bad Gateway - upstream unavailable
502 Bad Gateway|upstream prematurely closed connection
- •Verify the upstream server is running and listening on the expected address/port
- •Increase proxy_read_timeout and proxy_connect_timeout for slow backends
config3 fixes
Nginx 504 Gateway Timeout
504 Gateway Time-?out|upstream timed out.*reading response
- •Increase proxy_read_timeout (default 60s): proxy_read_timeout 300s
- •Optimize the backend endpoint that's taking too long to respond
config3 fixes
Nginx redirect loop
rewrite or internal redirection cycle|return 301.*too many redirects
- •Check for conflicting rewrite rules that redirect back and forth (HTTP→HTTPS→HTTP)
- •Use 'return 301' instead of 'rewrite' for simple redirects to avoid rule interaction