OK it's good!
The lan web server aswerd just with 443 port.
It must put "proxy_pass https://backend_toto.com;" instead of "proxy_pass http://backend_toto.com;".
The lan web server aswerd just with 443 port.
It must put "proxy_pass https://backend_toto.com;" instead of "proxy_pass http://backend_toto.com;".