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0 points_jal8y ago0 comments

I'm in the same boat - been running my own mail since the 90s. I could understand complaints about lots of weird hoops to jump through to get mail from your server accepted elsewhere - that has become harder over time[1] - but there's a very short list of things that need to be done to avoid being hijacked.

Mail server setup for the uninitiated does look a little daunting, especially if you're more accustomed to "all-in-one"-ish software. If you want to do this, I recommend starting with making sure you have a clear mental model of mail server architecture, especially where it touches other things (DNS, DKIM, spam filters, local delivery, probably IMAP, maybe LDAP, maybe databases, etc.) Without a clear idea of the dataflow and reasons for different decision-points, you're going to have a very bad time troubleshooting things.

[1] SBCGlobal.net has been rejecting me for over a decade despite there being zero spam ever having been emitted by my domain. Eh, my userbase communicates with exactly one SBC user; ATT can bite me.

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burgerdev8y ago

I've been running my mail server for 6 years now. Mail to Microsoft's servers (live.com, etc.) keeps ending up in the spam folder, even though spf, dkim and dmarc are set up and my IP has been clean for the entire period. The bright side is that I only notice this in the rare case of "mail to all contacts", since noone is on outlook.com these days.

cpncrunch8y ago

Yes, live.com is a problem for us too. It seems they silently blacklist ip addresses and make it very difficult to get off that blacklist. There's a thread here about it with some of us trying to figure out how to solve this problem:

https://answers.microsoft.com/en-us/outlook_com/forum/oemail...

But other than that, running my own mail server hasn't been much of an issue. Set up sendmail, use public blacklists for spam control, and it pretty much runs without any intervention.

megous8y ago

Outlook.com/Microsoft blacklists entire subnets because there are spammers in the same IP range. It's ridiculously lazy practice. They should just block IP addresses that are actually sending SPAM. It's not like that's a problem technically. You can fit all IPv4 addresses into a 512MB database.

I'm thinking of solving it by blacklisting outlook.com domain, so that senders at least know that I can't respond to them. I can put a message in the error response, that will be reliably relayed to the sender by the sending system.

Google's slightly better. Recently I did an experiment and created a few gmail accounts and sent some riduculously spammy messages full of typical keywords in between those gmail accounts, and they were all successfully delivered. Always.

Then I sent e-mail from new gmail account to my email server and simply responded and it went to spam. It's ridiculous that such a simple heuristic like someone responding to a message gmail user sends doesn't get the message through spam filters, even though the system can clearly determine taht the message is legit based on many variables (References field referencing message-id of the original message (noone else than the recipient should know this), reply being from a correct source (DKIM/SPF), message having normal looking business content, etc.).

There's way too heavy a weight on sending server IP range reputation.

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dasil0038y ago

On the plus side, do you really want to communicate with anyone who uses a SBCGlobal email address?

collinmanderson8y ago

That’s kind of harsh. I know a lot of people with sbcglobal addresses, and yes I want to communicate with them.

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