I have a raspberry pi running postfix. I Realised unless I open port 25 I absolutely cannot receive emails (I have 587 open and can send but not receive them). However I heard there are scaries online which someone could potentially send emails from your server without consent. I believe as well my ISP doesn’t block port 25. Is there anything I should do right now before opening port 25, or should everything be safe enough?
Ideally, don’t. Self-hosting email is complicated, easy to get wrong (and dangerously wrong, where people could use your server as an open relay and send spam).
That said, if you really want to, make sure you’re not accepting email except for what’s destined for you. There are a bunch of postfix best-practice guides out there that can be easily found with a Google search. I don’t host my own email, so I can’t vouch for any.
Agreed. I used to host email professionally and would not recommend managing your own mail server. It will constantly be under attack by spammers and if the inbox email address is exposed at all, soon 90% of incoming mail will be spam and you’ll need antispam software to filter it.
Not sure about you latter point tbh. I run an email server, with nothing but grey listing and spamassassin and the amount of spam is absolutely minimal.
Proper config and fail2ban easily takes care of direct attacks.
Nevertheless, I wouldn’t recommend it to anyone but the most determined.
To be fair, they said that you would need anti spam software and you do use anti spam software.
And even if you do everything 100% right, your emails will mostly get flagged as spam if not outright blocked anyway. Esp. if you’re using a residential IP.