Add the following to ~homeuser/.nailrc to set the default SMTP relay:
# Remote SDF SMTP relaying (use SDF 'mkvpm' tool to set auth user:pw): set ssl-verify="ignore" set smtp-use-starttls set smtp=mx.sdf.org:587 set smtp-auth=cram-md5 set smtp-auth-user="firstname.lastname@example.org" set smtp-auth-password="my_password"''
The SDF CA is self-signed but can still be used if desired. Retrieve and store somewhere (ie. under ~/.openssl/) as pem file, then edit ~homeuser/.nailrc like so:
set ssl-ca-file="/home/home_user/.openssl/sdf_self-signed_ca.pem" set ssl-verify="warn" # will issue "self-signed CA" warning ...
Account-specific smtp settings are possible; see the Heirloom Mailx documentation.