Tried your approach (How to Secure NGINX/RTMP stream to Facebook using Stunnel) but when I went to start stunnel, I got this output:
[ ] Clients allowed=500
[.] stunnel 5.56 on x86_64-pc-linux-gnu platform
[.] Compiled with OpenSSL 1.1.1c 28 May 2019
[.] Running with OpenSSL 1.1.1f 31 Mar 2020
[.] Threading:PTHREAD Sockets:POLL,IPv6,SYSTEMD TLS:ENGINE,FIPS,OCSP,PSK,SNI Auth:LIBWRAP
[ ] errno: (*__errno_location ())
[.] Reading configuration from file /etc/stunnel/stunnel.conf
[.] UTF-8 byte order mark not detected
[ ] "/etc/stunnel/conf.d/." is not a file
[ ] "/etc/stunnel/conf.d/.." is not a file
[.] Reading configuration from file /etc/stunnel/conf.d/fb.conf
[.] UTF-8 byte order mark not detected
[.] FIPS mode disabled
[ ] Compression disabled
[ ] No PRNG seeding was required
[ ] Initializing service [fb-live]
[ ] Ciphers: HIGH:!aNULL:!SSLv2:!DH:!kDHEPSK
[ ] TLSv1.3 ciphersuites: TLS_CHACHA20_POLY1305_SHA256:TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256
[ ] TLS options: 0x02100004 (+0x00000000, -0x00000000)
[ ] No certificate or private key specified
[!] error queue: ../crypto/x509/by_file.c:199: error:0B084002:x509 certificate routines:X509_load_cert_crl_file:system lib
[!] error queue: ../crypto/bio/bss_file.c:76: error:2006D080:BIO routines:BIO_new_file:no such file
[!] SSL_CTX_load_verify_locations: ../crypto/bio/bss_file.c:69: error:02001002:system library:fopen:No such file or directory
[!] Service [fb-live]: Failed to initialize TLS context
[ ] Deallocating section defaults
Just wondering what I may have done wrong, thought I had followed your instructions exactly, but may have forgotten something. Any suggestions?