mtbc: maze I (white-red)
Mark T. B. Carroll ([personal profile] mtbc) wrote2022-01-15 10:01 am
Entry tags:

Might should review mail server setup

Last week I found out why some e-mail that I had sent had gone missing: Cisco's IronPort had quarantined it. So much for, 250 Ok. Naturally, the product is rather opaque about exactly what offended it about my messages. My servers come up clear on blackhole lists and suchlike.

I like to try to keep my computing arrangements simple. For the most part, if I attempt to deliver RFC-compliant messages in an RFC-compliant way then I figure it's largely on the receiver if they fail to deliver the message properly. Nonetheless, if I must live in the real world then I also have to consider how typical practice evolves.

Some time ago, I caved to modernity by adding an SPF entry to my DNS, at least that is a simple act. Also, I bother to have a proper SSL certificate set up for my MTAs. I wonder if what upset IronPort may mostly have been a lack of DKIM or DMARC or somesuch. Perhaps there is an easy win from adding such a thing that I should be considering, especially if the tide is inexorable, or perhaps the issue was something else entirely.
emperor: (Default)

[personal profile] emperor 2022-01-15 04:02 pm (UTC)(link)
We enabled DKIM for transformativeworks.org and archiveofourown.org (which emits quite a lot of mail), and it did seem to improve the rate at which people actually got our mail. On a modern Debian exim setup, it's pretty easy to enable.