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?
What “someone else’s service” would you recommend?
Personally I’d probably go with MS hosted exchange or a Google business account. If you don’t trust those entities I’ve heard good things about ProtonMail - I imagine they have some kind of business solution.
Google and MS are the entities you’d definitely want to keep your data away from, no thanks. And Proton doesn’t work with normal mail clients, which is kind of a dealbreaker. I remember seeing a comparison chart somewhere with an assortment of other services.
There’s mailbox.org for example
Mango mail, porkbun, proton mail
Each does a slightly different niche.
Mango is cheap, but limits outbound mail. Porkbun has a good all-around mail service, bit is a little more costly. Proton is very secure, but can be inconvenient for export (though it can be done, it requires purchase of a month of business service to export away from them).