fix(mail): localhost/self SMTP relay uses direct-MX (no relay-to-itself loop)#23
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…self Setting the SMTP relay host to localhost (e.g. via "Detect local SMTP relay", which pre-fills localhost:25) made Hyperion configure postfix with relayhost=[localhost]:25 — i.e. relay through itself. postfix then defers every message with "mail for localhost loops back to myself", so the panel shows "sent" (postfix returned 250 on submission) but nothing is ever delivered and the mail sits in the queue forever. A relay host that points at THIS node (localhost / a loopback IP / our own short or fully-qualified hostname) isn't a smart-host at all — sending "via the local postfix" IS direct-MX delivery. Add postfix::host_is_local() and route such a config to ensure_direct_delivery_config() instead of ensure_relay_config at BOTH decision points: the mta-reconfigure RPC (service.rs) and the agent-boot apply (main.rs), so an agent restart can't reintroduce the loop. clippy -D warnings clean; new host_is_local unit test + adapters suite green. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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…op could return (#27) The boot-time postfix self-heal decided smart-host vs direct-MX by calling host_is_local(smtp_host, agent_hostname) with the SHORT hostname (`hostname`), while the runtime mta_reconfigure path correctly uses `hostname -f`. So a relay set to the node's OWN fqdn (e.g. `s4.example.com` on host `s4`) slipped past host_is_local at boot into relayhost=[s4.example.com] — the exact "mail for localhost loops back to myself" self-relay loop #23 fixed. And since EmailConfigSet self-restarts the agent, that buggy boot path re-ran after every mail save, silently undoing the correct decision mta_reconfigure had just made. Fix: - Boot resolves the FQDN once (via `hostname -f`, short-name fallback) BEFORE the smart-host decision and passes it to host_is_local — matching the runtime path. Also removes the now-duplicate `hostname -f` block in the direct-MX arm. - Defense in depth: host_is_local also catches a relay typed as our full fqdn when we only know our SHORT name (degraded `hostname -f`), via a short-label compare scoped to that case only — a legit external relay sharing our short label (our mail.acme.com vs relay mail.sendgrid.net) is still a smart-host once we know our real fqdn. clippy -D warnings clean; host_is_local self/loopback + degraded-short-fqdn unit tests green. Co-authored-by: mkn <matej@nechodom.cz> Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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The bug (from your mailq)
Relay host =
localhost→ Hyperion wrote postfixrelayhost=[localhost]:25→ postfix relays through itself → every message defers with "mail for localhost loops back to myself". The panel shows "sent" because postfix returned 250 on submission, but nothing is ever delivered and it piles up in the queue.Fix
A relay host that points at this node (localhost / loopback IP / our own short or FQDN hostname) isn't a smart-host — "send via the local postfix" is direct-MX delivery. New
postfix::host_is_local(); both decision points route such a config toensure_direct_delivery_config()instead ofensure_relay_config():service.rs), andmain.rs) — so a restart can't reintroduce the loop.Note for real delivery
This stops the loop, but direct-MX from a VPS usually still won't reach an inbox (blocked port 25 / no SPF-PTR-DKIM). For mail that actually lands, point the relay at a real provider (Postmark/Mailgun/SendGrid/Brevo/Gmail) in Settings → Mail.
Test
clippy -D warningsclean; newhost_is_localunit test (localhost / 127.x / ::1 / short + FQDN self vs. real relays) + adapters suite green.🤖 Generated with Claude Code