List of paths to the server private keys and certificates.
The order of items matters and a private key must always be followed by the corresponding certificate.
https://www.postfix.org/postconf.5.html#smtpd_tls_chain_files.
Declarations
Type
list of absolute path
Default
[ ]
Example
[
"/var/lib/acme/mail.example.com/privkey.pem"
"/var/lib/acme/mail.example.com/fullchain.pem"
]