Build log · Phase 17

A Real Mail Admin Toolkit

July 26, 2026 · 2 min read · kritchie

Same day as the DNS roadmap closing out, the mail side of the Controller area went from “the basics work” to a genuine admin toolkit — the kind of pages a mail admin reaches for when something’s wrong or needs tuning, not just account/mailbox CRUD.

Outbound relay (smarthost)

Route this server’s outbound mail through a third-party relay instead of sending directly — the credential is encrypted at rest and never redisplayed after saving.

Mail server configuration

Which protocols are enabled, TLS policy, and process limits — all editable without touching a config file over SSH, applied through a fully-managed configuration.

Mail Queue Manager

Every message currently queued, with the reason a deferred message hasn’t gone out yet. Retry one message or the whole queue, or clear it. Verified against a real deferred message on a development server.

Delivery reports and mail statistics

Search the mail log for a specific message’s delivery history, or browse recent activity. A statistics view aggregates sent volume by domain and lists authenticated relay logins — useful for spotting unusual volume.

Filter incoming email by domain or country

Reject incoming mail from a specific sender domain, or from an entire country’s IP ranges, at the SMTP level — confirmed with a real blocked connection attempt.

Greylisting

Temporarily defers mail from senders the server hasn’t seen before. Real mail servers retry automatically within a few minutes; most spam-sending software doesn’t. Confirmed live with a real non-local connection.

Spam filtering

Content-based scoring, wired in as an additional mail filter alongside the DKIM signing already running. Verified with the standard industry spam-test string, confirming the message was tagged.

Repair Mailbox Permissions, Autoresponders, and Email Deliverability

One-click repair when a mailbox’s file ownership drifts and mail stops delivering; per-mailbox autoresponders built on the mail server’s own standard extension; and a per-domain check of SPF, DKIM, DMARC, and reverse DNS, reachable from the same area as the existing nameserver diagnostic.

The pattern, still holding

Every one of these was tested against a real running development server, not mocked. A few infrastructure gaps turned up along the way, and each was fixed the same day it was found.

Phase 17 of 269The build log so far

Every phase, from the beginning →

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