Hi, I have some hardware which I've configured to send e-mails through my Postfix server. Unfortunately, this hardware's firmware has its' EHLO command hardcoded, not being it an FQDN.
In Postfix, I've configured smtpd_helo_restrictions to have reject_non_fqdn_helo_hostname and I'm pretty happy with it so I don't want to remove it, however it makes its' attempts to get rejected. Another issue is that it's connections are made from a dynamic IP address, so whitelisting its IP address is not an option. However, it has a dynamic hostname which updates each time it changes (a DynDNS-like host). I know I can't add hostnames to $mynetworks, so my last resource would be writing a policy service which would check the client's IP address and match it with the dynamic hostname, and if positive, accept the EHLO command before it reaches the reject_non_fqdn_helo_hostname restriction. I'd like to know if there's a simpler way to handle these kind of situations, though. Do you guys have some tips? Thanks. Nicolás
