Da Supporto Cloudflare - Domande frequenti SSL :
What do the SSL options mean?
Your domain's SSL option determines how Cloudflare connects to your server either using encryption or not.
Flexible SSL:
SSL is terminated at the Cloudflare edge servers. Everything between your client and Cloudflare is encrypted, but between Cloudflare and your origin server is not encrypted. You would not need a certificate directly installed on your server for full encryption.
SSL Full:
SSL is terminated at the Cloudflare edge server. Then it is encrypted again, and sent back to your servers all encrypted. You would need an SSL certificate installed directly on your server for this option. You can also use a self-signed certificate for this option.
SSL Full Strict:
Same as SSL Full, but you must have a trusted certificate that is signed by a valid Certificate Authority (such as GlobalSign or DigiCert).
Custom SSL (Business/Enterprise ONLY)
Customers on these plans are able to upload their own SSL key and certificate, so CloudFlare's name will not show if a visitor checks the certificate.
Quindi, finché il tuo dominio utilizza l'opzione "SSL Full" o "SSL Full Strict", il traffico dovrebbe essere crittografato da Cloudflare al tuo server.
Perimpostarequestaopzione,vaialladashboarddiCloudflareperiltuodominio,selezionailpannello"Crypto" e cambia l'opzione SSL dal valore predefinito di "Flessibile" a "Completo (rigoroso)". Poiché utilizzi Let's Encrypt sul server di origine, la modalità rigorosa dovrebbe essere accettabile per te.
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