The recommended TLS configuration comes with `ssl_stapling on` and
`ssl_stapling_verify on`. However, this last directive also requires
the use of `ssl_trusted_certificate` to verify the received answer.
When using `enableACME` or similar, we can help the user by providing
the correct value for the directive.
The result can be tested with:
openssl s_client -connect web.example.com:443 -status 2> /dev/null
Without OCSP stapling, we get:
OCSP response: no response sent
After this change, we get:
OCSP Response Data:
OCSP Response Status: successful (0x0)
Response Type: Basic OCSP Response
Version: 1 (0x0)
Responder Id: C = US, O = Let's Encrypt, CN = Let's Encrypt Authority X3
Produced At: Aug 30 20:46:00 2018 GMT
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