> On 04-23-2022 9:58 pm, ミユナ wrote: > does plain traffic on port 25 require a certificate?
That is optional and up to you if you want connections to use STARTTLS. Look into the following settings: smtpd_tls_security_level smtp_tls_security_level smtpd_tls_cert_file smtpd_tls_key_file
