Confirmed on the operator's NAS. The earlier advice (insert an ACCEPT rule
ahead of DSM's chain) does not hold: DSM reloads its firewall periodically,
flushing and rebuilding the chains. You can watch FORWARD_FIREWALL's DROP
counter reset to zero and the inserted rule vanish with it, having matched no
packets. That is also why the symptom looked intermittent — 60/40 success on
repeated connections, with RELATED,ESTABLISHED keeping existing flows alive.
The fix is one level down: net.bridge.bridge-nf-call-iptables=0 takes
same-bridge traffic out of iptables entirely, so DSM's reloading cannot affect
it. Persisted with a Boot-up Triggered Task.
Section 8 now also answers "is that safe", accurately: the flag affects only
packets bridged within one network. Traffic between different Docker networks
is routed, so DOCKER-ISOLATION still applies; inbound traffic to published
ports is still routed and still firewalled; INPUT, which protects the NAS
itself, is untouched. The one real caveat is that it is host-wide, so VMs
sharing a bridge lose same-bridge filtering too.
The migrate failure message points at the sysctl now.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Nux3LCu4zP9nih4BRhPyHw
Diagnosed on a real Synology: with the DSM firewall enabled, iptables reads
-A FORWARD -j FORWARD_FIREWALL <- DSM, first, default deny
-A FORWARD -j DEFAULT_FORWARD <- Docker's ACCEPT rules, never reached
and bridge-nf-call-iptables=1 sends container-to-container packets through
FORWARD. A new connection to postgres:5432 matches no DSM allow rule and is
dropped before Docker's own "-i docker-xxx -o docker-xxx -j ACCEPT" is
consulted. RELATED,ESTABLISHED is accepted, which is why the port could test
open from a throwaway container while every new connection timed out — the
symptom looked intermittent and pointed nowhere near the firewall.
- docs §8: the diagnosis, the one-line fix
(iptables -I FORWARD 1 -i docker+ -o docker+ -j ACCEPT), a boot-up Triggered
Task so it survives reboots and firewall reloads, and a verification command.
- The migrate failure message now names this cause and the fix, since that is
the error an operator actually sees.
Nothing in the stack is at fault here; this is host firewall configuration.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Nux3LCu4zP9nih4BRhPyHw
On a Synology first run, migrate exited with "postgres:5432 never accepted a
connection" after the full 180s — and that was the entire diagnostic output,
despite the network being demonstrably fine afterwards (postgres resolved and
port 5432 was open from a throwaway container on the same network).
The retry loop caught OSError and discarded it. It now prints the first
failure immediately and repeats every 30s, with the hostname's resolved
address alongside, and includes the last error in the final message. A
DNS failure, a refused connection and a silently dropped packet each produce
a different line instead of the same useless one.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Nux3LCu4zP9nih4BRhPyHw
On a real Synology first run, `migrate` exited 1 with a bare asyncpg
TimeoutError while the postgres log showed a perfectly healthy server.
The healthcheck was `pg_isready` with no -h, so it checked the UNIX SOCKET.
During first-time initialisation the postgres image runs a temporary server
that listens on the socket only (listen_addresses=''), so pg_isready answered
and the container was marked healthy while nothing was listening on TCP yet.
Dependents then connected to postgres:5432, hung, and timed out. It only bites
on the very first start of a fresh data directory, which is exactly the run an
operator is doing when they have least idea what is wrong.
- healthcheck uses `pg_isready -h 127.0.0.1 -p 5432`, so health means TCP is
actually accepting.
- `migrate` additionally waits for the port itself (DB_WAIT_SECONDS, default
180) before running alembic. It is a one-shot with no restart policy, so a
few seconds of slow NAS disk should not fail the whole bring-up; the API and
workers already self-heal through their restart policy.
Verified with a first-time bring-up against a fresh data directory: migrate
logs "database accepting connections", applies core + all four plugin
branches, and the stack comes up serving.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Nux3LCu4zP9nih4BRhPyHw
Everything needed to run the app on an Intel NAS that is also doing other
jobs: one published port, no host networking, memory/CPU caps and log
rotation on every container, and all state in bind mounts under DATA_ROOT
so mail survives image updates, project deletion in the NAS UI, and full
reinstalls — and so Hyper Backup/HBS3 can actually see it.
- docker/Dockerfile.backend: multi-stage, non-root (uid 10001), tini for
the <10s graceful lease release. Installs the four plugins as entry-point
distributions. One image, several roles via docker/entrypoint.sh
(api | worker-sync | worker-jobs | migrate | reindex | plugins).
- docker/Dockerfile.frontend + nginx.conf: SPA + /api reverse proxy with
the WebSocket upgrade for /api/ws, and X-Forwarded-Proto preserved so
the API still emits __Host-/Secure cookies when TLS is terminated by
the NAS reverse proxy (identity/cookies.py keys off request scheme).
- docker/docker-compose.prod.yml: project name webmail-prod, NOT webmail —
docker-compose.yml (dev services) owns that name, and two compose files
sharing one project name fight over each other's containers.
Meilisearch is an opt-in profile; SEARCH_BACKEND=pg is the default so a
small NAS pays nothing for search.
- migrate runs as a one-shot (core Alembic head + every plugin branch)
that everything else waits on, so a bad migration can never leave new
code running against an old schema.
- docker/backup.sh: nightly pg_dump verified with `pg_restore --list`
before it counts as a backup, with retention and a baseline on first
start.
- deploy/webmail.sh: init/doctor/up/down/status/logs/update/rollback/
backup/restore/reindex/psql/shell. `update` is backup -> images ->
migrate -> roll workers, api, web -> health-gate, with automatic
rollback to the previous version if the gate fails. `doctor` refuses to
be quiet when DATA_ROOT is on NFS/SMB (silent Postgres corruption).
- deploy/build-push.sh: build images off-NAS (the frontend build wants
~2GB RAM) and push to Gitea, or --save a tar to carry over.
- scripts/reindex_search.py: rebuild the search index from Postgres alone.
Every SearchDoc field is already stored, so the index is derived data
that never needs backing up — this closes the only real objection to
running Meilisearch on a box whose volumes may be wiped.
- pyproject: package-data for accounts/presets.yaml and the shared plugin
Alembic env. Without it a non-editable install (i.e. any image) silently
ships a package that fails at runtime.
- GET /api/version, used by the deploy health gate.
Verified end to end on a real stack: fresh install, all services healthy,
core + 4 plugin migration branches applied, login/SPA/plugin bundles
through nginx, WS upgrade returning 101, __Host- cookies under a
simulated TLS proxy, backup -> restore round-trip preserving user and
plugin schema, failed-update auto-rollback (both a bad migration and a
boot-crashing API), and Meilisearch profile serving a live query.
ruff + mypy --strict clean, 363/363 backend tests pass.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Nux3LCu4zP9nih4BRhPyHw
lukasandClaude Opus 5