No official way exists, however if you don’t mind something a little hacky for the time being, have a look at my topic Using nginx/pi-hole to reverse proxy (the dodgy way)
Specifically, referring the code for /root/scripts/nginx-proxy.sh, which allows you to inject a custom config into Rockstor’s own nginx, included in the ‘http’ section.
You should then be able to specify your own cipher suite list using the following statements:
- ssl_prefer_server_ciphers
- ssl_protocols
- ssl_ciphers
Cheers,
Hayden.