SMTP Relay Questions
SMTP Relay Questions
I use O365 Business (Or whatever the heck they call it now) for my email, so for SMTP on all my devices at home, I use an O365 account with an app password, sending as a distro-group so it can have a custom name
This works, but I don't like how every device/server has O365 creds in it. I am thinking I should setup an SMTP Relay at home locally, which sends to O365 (Or Sendgrid, etc etc) and then SMTP on local services can just point to that local address
Is this the right way to go about it? What is the current best software do it? I've only ever had experience using IIS to do this, and of course I don't want to be running windows!
Interactive (i.e. end-users) Clients should be using OAuth instead of app passwords. This will allow your users to use their own Office365 credentials for SMTP.
For servers and non-interactive clients (e.g. copiers/printers/toasters/coffee makers) I would suggest something along the lines here: https://learn.microsoft.com/en-us/exchange/mail-flow-best-practices/how-to-set-up-a-multifunction-device-or-application-to-send-email-using-microsoft-365-or-office-365#compare-the-options
I use https://github.com/YoRyan/mailrise
Mailrise is apprise under the hood. It's an SMTP server that converts all the emails it receives to push messages depending on the To address in the email.
I think what you're doing is fine, in fact, it's one of the Microsoft recommended methods of doing it.
I've started using SMTP2GO for all my notification. Up to 1000 email/month it's free. So I don't have to rely on Google/Microsoft account/changes that they do every once in a while.
In my case I have postfix running as an open relay inside my network that then relays to Amazon SES. But I have my own domain.
I imagine doing something similar where you relay to o365 might work.
If you are just sending notification emails to your own account then you can use SMTP directly to O365 without authentication and it will be delivered as long as it’s being sent within your tenant (if your home IP isn’t in your SPF record it may get delivered to junk however)
This is how we handle scan to email using MFPs in our org. No credentials, or even a mailbox for the outgoing sender, required
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
Fewer Letters More Letters DNS Domain Name Service/System IP Internet Protocol SMTP Simple Mail Transfer Protocol
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Best bet would be to setup postfix or opensmtpd as an open relay. Just make sure it is only accessible in trusted networks though!!
https://docbot.onetwoseven.one/services/postfix/
You’d want to set the listen address to 0.0.0.0 and use a non-loop back interface.
Just make sure it is only accessible in trusted networks though!!
Aw you're no fun. Next you'll be telling me to block all emails over 500 miles.
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An unauthenticated relay isn't a security problem when it can only send to certain addresses in 365, and isn't even accessible outside the local network.