On Tue, May 31, 2022 at 01:05:57PM +0200, Maurizio Caloro wrote: > Today create new my key file RSA, and ECDSA, and signed with certbot. > > ## TLS/SSL > /etc/letsencrypt/live/nmail.caloro.ch/privkey.pem > /etc/letsencrypt/live/nmail.caloro.ch/fullchain.pem
What does "TLS/SSL" mean? > ## RSA Key > /etc/letsencrypt/live/nmail.caloro.ch-rsa/privkey.pem > /etc/letsencrypt/live/nmail.caloro.ch-rsa/fullchain.pem These are the same as the below. > ## ECDSA Key > /etc/letsencrypt/live/nmail.caloro.ch-rsa/privkey.pem > /etc/letsencrypt/live/nmail.caloro.ch-rsa/fullchain.pem These are the same as the above. > [main.cf] > smtpd_tls_chain_files = > /etc/letsencrypt/live/nmail.caloro.ch/privkey.pem, > /etc/letsencrypt/live/nmail.caloro.ch/fullchain.pem, What key type is this? > /etc/letsencrypt/live/nmail.caloro.ch-rsa/privkey.pem, > /etc/letsencrypt/live/nmail.caloro.ch-rsa/fullchain.pem Perhaps both are RSA keys? You can only have on certificate per key type. > # smtpd_tls_cert_file = > /etc/letsencrypt/live/nmail.caloro.ch-rsa/privkey.pem > # smtpd_tls_key_file = > /etc/letsencrypt/live/nmail.caloro.ch-rsa/fullchain.pem > # smtpd_tls_eccert_file = > /etc/letsencrypt/live/nmail.caloro.ch-ecdsa/privkey.pem > # smtpd_tls_eckey_file = > /etc/letsencrypt/live/nmail.caloro.ch-ecdsa/fullchain.pem When you specify "chain_files", you should not also attempt to specify "key_file", "cert_file", "eckey_file" and "eccert_file", because these are superseded by "chain_file" and ignored. > smtpd_tls_received_header = yes > smtpd_tls_CAfile = /etc/ssl/certs/ca-certificates.crt You don't need an "smtpd_tls_CAfile" unless you're soliciting client certificates, and even then don't specify the standard trust bundle, that causes the TLS handlshake to bloat with the complete list of trusted CA names... > -- thanks for any update The update remains: stick to just one key type for now. -- Viktor.