ESMTPD(8)

✨ ESMTPD(8) ✨

okay bestie, gather round 💖 this is the manual for esmtpd — the Courier mail server's ESMTP daemon — and honestly? it's giving "small command, big job". Author energy throughout is S. Varshavchik, and yes we're gonna give credit where it's due at the end. 🎀

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🌸 NAME 🌸

esmtpd — the Courier mail server mail server ESMTP daemon 💅 (yes it says "mail server mail server", that's just how the original vibes, we're not touching it, it's iconic)

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🦋 SYNOPSIS 🦋

esmtpd {start}

esmtpd {stop}

esmtpd {restart}

esmtpd-msa {start}

esmtpd-msa {stop}

esmtpd-msa {restart}

like, pick one of those six, bestie, that's the whole thing 🌈

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👑 DESCRIPTION 👑

so here's the tea ☕

The command esmtpd start runs couriertcpd in the background, listening on the SMTP port. And then couriertcpd will run courieresmtpd in response to connection requests. That's the whole pipeline, no cap 🔥

The command esmtpd stop stops the couriertcpd daemon, shutting down the ESMTP service. bye bestie 👋 and it means it, the whole service goes down.

The command esmtpd-msa start starts the server on the message submission port, port 587. And esmtpd-msa stop stops it. Classic start/stop duo. 💫

The difference between esmtpd and esmtpd-msa? The latter is set up for additional processing as defined by RFC 2476 — mainly that the messages will have the Message-ID: and Date: headers added, by default. so it's the same server but with extra ✨ pizzazz ✨

Normally, makesmtpaccess(8)[1] automatically runs esmtpd restart, in order to reread the /etc/courier/smtpaccess.dat access file, so you don't have to do it manually, yourself. Like, it does it for you. scream. 😭

Similarly, makesmtpaccess-msa(8)[1] automatically runs esmtpd-msa restart. 🫶

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🎀 FILES 🎀

• /etc/courier/esmtpd — This configuration file initializes various settings for courieresmtpd. the main character config file 💜
• /etc/courier/esmtpd-msa — This configuration file initializes the settings for courieresmtpd when invoked by esmtpd-msa. Note that this file is used to override the settings in /etc/courier/esmtpd. The command esmtpd-msa start first reads /etc/courier/esmtpd, then afterwards /etc/courier/esmtpd-msa. Any settings in esmtpd-msa override the corresponding settings in esmtpd. so like, read order matters, the second one wins 🏆

lowkey important: it's not a merge-fest where both confuse each other — esmtpd-msa settings straight up override the matching esmtpd ones. periodt. 💅

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🌈 SEE ALSO 🌈

• couriertcpd(8)[2]
• makesmtpaccess(8)[1]

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💖 AUTHOR 💖

Sam Varshavchik

• Author

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📝 NOTES 📝

1. makesmtpaccess(8) — https://www.courier-mta.org/makesmtpaccess.html
2. couriertcpd(8) — https://www.courier-mta.org/couriertcpd.html

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and that's the whole page bestie, we ate and left no crumbs 🍓 this was Courier Mail Server, dated 01/10/2026, no cap — go forth and run your ESMTP daemon responsibly, ilysm 🧚💜