What's the best configuration for a web server that does not receive mail but needs to send mail? Password resets. Bug ticket update notifications. That type of email. (Plus admin mail such as cron output to root. But I can ensure that is delivered to me and read.) But the host never needs to receive email from the public. Just outgoing. Is this about what you would think too?
o SPF configured o DKIM configured o DMARC set as p=none o No MX records o inet_interfaces = loopback-only But some mail configuration testing sites (such as mail-tester.com) flag sites that send but do not have an MX record for receiving mail. Presumably because there is no way for a separate bounce notification message to be sent, even if that isn't desirable. But a reject at SMTP time is always available. Strategy wise is an MX record now a required thing for sending mail like some test sites say? If so then I should set up one. And arrange for some system somewhere, perhaps this one but probably a different one, to receive incoming mail for it. But with what configuration? A catchall that accepts and silently discards all incoming mail perhaps so as to pass sender address verification? I am lost at sea thinking of this possible requirement for hosts that do sender address verification types of things. I would appreciate any wisdom that might be shared here with regards to a strategy for this type of web site system. Thanks! Bob
