Hello, ED. From your response, I'm not entirely sure if I explained my intent properly.
Sorry if I'm just being dumb, but to clarify: I'm running OpenBSD in a VM on my home machine in hopes of getting better acquainted with the OS for later use in a VPS hopefully. From the VM, I'm trying to send a basic test mail to, for example, any Gmail address. I'm not expecting any inbound mails to the VM (i.e. a "do-not-reply", outbound-only mailer). I'm using the default smtpd.conf file, so if I've understood the documentation correctly, it should be trying to perform MX lookups instead of relying on an external SMTP service, right? I've read that this should be doable anyway? Albeit higher risk of being flagged as spam. So, theoretically, if my ISP did not block port 25, would I then be able to send a mail without the need for an external SMTP service? Or would I likely be getting other errors? Please forgive my lack of knowledge on e-mail protocols and networking in general, and thanks so much for your time! On 4/22/2021 at 10:01 PM, "ED Fochler" wrote:No. You're only trying to send mail. Your ISP is only trying to stop you from sending mail. Mail delivery is meant to be very well defined and easy to identify. If your ISP is blocking connections to port 25 then they are blocking all mail, spam and otherwise. The solution is to set up a mail server on a network that allows mail. This can be a $5/mo cloud server. You can then 'submit' mail to your mail server using other ports, but the mail server will talk to other mail servers on standard ports, primarily port 25. ED. > On 2021, Apr 22, at 3:18 PM, [email protected] wrote: > > Hi. Is it possible to configure smtpd to relay via a port other than port 25? Since my ISP is blocking port 25, it seems smtpd is failing to perform MX lookups (or some other step?) when I try to send mail, as seen via "tail -f /var/log/maillog". At least, the only solution I've succeeded with so far is to use an external SMTP service (whereby a different port can be set), which I'm trying to avoid if possible. I'm only trying to send mail, nothing else. > > Sample maillog output: > > Apr 22 21:02:12 openbsd smtpd[85598]: smtp-out: Enabling route [] x.x.x.x > Apr 22 21:02:12 openbsd smtpd[85598]: smtp-out: x mta connecting address=smtp://x.x.x.x:25 host=x > Apr 22 21:02:12 openbsd smtpd[85598]: smtp-out: x mta error reason=Connection timeout > Apr 22 21:02:12 openbsd smtpd[85598]: smtp-out: Disabling route [] x.x.x.x > Apr 22 21:02:27 openbsd smtpd[85598]: smtp-out: Enabling route [] x.x.x.x > Apr 22 21:02:27 openbsd smtpd[85598]: smtp-out: x mta error reason=IO Error: No route to host > Apr 22 21:02:27 openbsd smtpd[85598]: smtp-out: Disabling route [] x.x.x.x > Apr 22 21:02:27 openbsd smtpd[85598]: smtp-out: x mta connecting address=smtp://x.x.x.x:25 host=x
