Am 01.06.2020 um 19:44 schrieb Jerry Geis: > I am looking for a way for sendmail to ALLOW auth by IP and not user name > (its a closed network) or even SKIP invalid auth ? > Is that even possible ? It is possible to configure Sendmail to relay based on client connection. The doc will tell you how. https://www.sendmail.org/~ca/email/doc8.12/cf/m4/anti_spam.html#access_db If your Sendmail setup demands AUTH, then it will not skip in case of false credentials. Whatever backend you configure cyrus-sasl to use for validating the SMTP AUTH credentials, it is possible to use other values than a user name. > Jerry Alexander