Certificate source for OCSP Stapling in Nginx?

Question

Nginx

I received a certificate for the site from the Chinese company WoSign according to instructions from Habr. There was also a recommendation to avoid lengthy requests for certificate confirmation in China to configure OCSP Stapling . I took this article as a base . Everything is clear and understandable, except for the moment - where to get the certificate " root and intermediate CA certificate in PEM format " from.
Does this mean the usual chain of CA certificates, which is already in the certificate received for the site and is already used in the server 's ssl_certificate directive ? Those. is it enough to remove the site's PEM certificate from the received bundle and use it in this form in the ssl_trusted_certificate directive? If this is indeed the case, then why did the creators of NGinx make such a strange duplication mechanism, and not use the data that they already have? Or do you still need some other certificates?

Answer 1

Well, let's take and read the documentation:
What is not clear? ssl_trusted_certificate is only used when OCSP stapling is enabled. And only if root and intermediate are not in ssl_certificate.