@aluaces Thanks. Realized that what I really don't want is to extend this server into mail service, for a lot of reasons. Monday I'll propose to install it it on a small dedicated cloud computer. wish you a good weekend.

@mc Not sure if I get your point, but anyway msmtp, smtpd or even sendmail if I recall correctly can be used to contact and deliver mail to an external SMTP server which does the actual work.

Have also a good weekend!