ops: systemd supervision for Core and the FIFA17 host (staging-proven)

Replaces the detached `setsid nohup … nsenter …` launch, which had no restart
policy, no boot persistence and no supervisor-visible logs. Staging units are
installed and proven; production units are TEMPLATES and are not installed.

Three decisions, each measured rather than assumed:

* `Wants=`, not `Requires=`, from host to Core. With `Requires`, stopping Core
  stopped the host AND a later Core start did not bring it back -- a routine
  Core restart would leave the client with no server. With `Wants` the host
  survives a Core outage, answers 503 core_unavailable, never falls back to
  Python, and resumes the moment Core returns with no intervention. Both halves
  tested.
* Readiness is a bounded ExecStartPre TCP gate, because ordering proves nothing
  about readiness and Type=exec only proves the binary exec'd. Core binds its
  listener after migrations and content load, so "port open" is a real signal.
  The gate FAILS rather than blocking: a host that waits forever looks healthy
  while serving nobody.
* The netns is resolved by container NAME every start. The container is
  restart=unless-stopped and its netns inode CHANGES on restart (measured:
  4026539938 -> 4026540033), so a hardcoded pid is wrong by construction and
  anything left in the old namespace serves nobody. Proven equivalent to today's
  nsenter against a scratch container, never production's namespace.

`systemd-analyze verify` caught two real defects before deployment:
StartLimitIntervalSec/StartLimitBurst sat in [Service], where systemd 252
silently ignores them, so the crash-loop ceiling was not taking effect; and a
Documentation URL containing %20 parsed as a specifier. Both fixed and the
effective properties re-confirmed from the running units.

Staging evidence: Core-first ordering, host refused when Core is absent or
merely not listening, outage survival, automatic recovery, restart, graceful
stop with no strays, boot simulated via multi-user.target, 3x SIGKILL contained
at ~5s spacing, journald logs, and economy state byte-identical throughout
(integrity ok, fk 0).
This commit is contained in:
funman300
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parent 9026220533
commit 8ae432223a
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# OpenFUT systemd units
Supervision for OpenFUT Core and the FIFA17 UTAS host. Replaces the previous
`setsid nohup … nsenter …` launch, which had no restart policy, no boot
persistence and no supervisor-visible logs.
| file | scope | installed? |
|---|---|---|
| `openfut-staging-core.service` | staging Core, port 18081 | **yes** — proving ground |
| `openfut-staging-host.service` | staging host, port 8299 | **yes** |
| `openfut-netns.service` | publishes the container netns to `/run/netns/openfut` | template only |
| `openfut-core.service` | production Core, port 18080 | template only |
| `openfut-host.service` | production host, port 8099 | template only |
| `openfut-netns-bind.sh` | resolves the container netns by NAME, idempotently | helper |
| `openfut-wait-tcp.sh` | bounded readiness gate | helper |
Production templates are **not installed**. Deploy only via the plan in
`OpenFUT-Vault/06 Operations/OpenFUT Service Supervision (staging-proven).md`.
## The three decisions worth knowing
**1. `Wants=`, not `Requires=`, from host → Core.** Measured on staging:
`Requires` propagates a Core stop into a host stop, and a later Core start does
*not* bring the host back — a routine Core restart would leave the client with
no server. With `Wants`, the host survives a Core outage, answers
`503 core_unavailable` (never a Python fallback), and resumes the moment Core
returns, with no supervisor intervention.
**2. Readiness is an `ExecStartPre` TCP gate, not ordering.** `After=`/`Wants=`
order units; `Type=exec` only proves the binary exec'd. Neither means Core can
serve. Core binds its listener *after* opening the DB, running migrations and
loading the content pack, so "port open" is a genuine readiness signal. The gate
is bounded and *fails* rather than blocking: a host that waits forever looks
healthy to the supervisor while serving nobody.
**3. The netns is resolved by container NAME at every start.** Production must
run inside `openfut-fut-backend`'s network namespace. The container is
`restart=unless-stopped`, and its netns inode *changes* on restart — observed
`net:[4026539938] → net:[4026540033]`. A hardcoded pid is therefore wrong by
construction, and any process left in the old namespace keeps running with no
interfaces, silently serving nobody. `openfut-netns-bind.sh` re-resolves by name
and refreshes a stale bind mount; `NetworkNamespacePath=` then enters it
declaratively.
> **Still open:** a container restart strands *already-running* services in the
> dead namespace. Re-running `openfut-netns.service` plus restarting Core/host
> repairs it, but nothing triggers that automatically yet. See the promotion
> plan's "Residual gap".
## Operating
```bash
systemctl status openfut-staging-core openfut-staging-host
journalctl -u openfut-staging-core -f
sudo systemctl restart openfut-staging-core # host survives and recovers
sudo systemctl stop openfut-staging-host openfut-staging-core
```
Config lives in `EnvironmentFile`s (`…/systemd/core.env`, `host.env`), generated
from the live process environment so supervision changed *how* the processes
start and nothing about *what* they do. Binaries are immutable copies, so a
later `cargo build` cannot change what is running.
## Interaction with the staging lifecycle script
`scripts/sold-staging-up.py` still starts its own unsupervised processes and
refuses to run while a staging stack is up. Stop the units first:
```bash
sudo systemctl stop openfut-staging-host openfut-staging-core
python3 scripts/sold-staging-up.py --club real --variant highest …
```
Reconciling the two (having the script drive the units) is deliberately out of
scope for the supervision milestone.
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[Unit]
Description=OpenFUT Core (PRODUCTION) — authoritative economy state
Documentation=file:///home/alex/OpenFUT/scripts/systemd/README.md
# PRODUCTION TEMPLATE — NOT INSTALLED. Deploy only via the promotion plan in
# `06 Operations/OpenFUT Service Supervision (staging-proven).md`.
#
# Core is the SINGLE WRITER of prod-core.db (verified by lsof: exactly one
# process holds it open). Nothing here may be templated into a second instance.
After=network-online.target docker.service openfut-netns.service
Wants=network-online.target
Requires=openfut-netns.service
# StartLimit* MUST live in [Unit]: systemd 252 silently IGNORES them in
# [Service] (`systemd-analyze verify` flags it), which would have left the
# crash-loop ceiling at the 10s/5 default instead of the intended 60s window.
StartLimitIntervalSec=60
StartLimitBurst=5
[Service]
Type=exec
# root, matching the current production processes exactly. Supervision changes
# HOW the process is started, never what it is or what it can reach.
User=root
# The container's netns, published by openfut-netns.service. This replaces the
# hand-typed `nsenter --net=/proc/<pid>/ns/net` in the runbook: same namespace,
# no hardcoded pid, and re-resolved on every start.
NetworkNamespacePath=/run/netns/openfut
EnvironmentFile=/etc/openfut/core.env
# An IMMUTABLE promotion artifact, not target/release. A later `cargo build`
# must not be able to change what production is running — the same invariant
# the promotion process already relies on.
ExecStart=/home/alex/openfut-migration/promote-contract-20260822-184409/artifacts/openfut-core
KillSignal=SIGTERM
KillMode=mixed
# Generous, so a WAL checkpoint is never SIGKILLed mid-write. Observed shutdown
# is sub-second.
TimeoutStopSec=30
Restart=on-failure
RestartSec=5s
StandardOutput=journal
StandardError=journal
SyslogIdentifier=openfut-core
[Install]
WantedBy=multi-user.target
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[Unit]
Description=OpenFUT FIFA17 UTAS host (PRODUCTION) — client-facing, Core-dependent
Documentation=file:///home/alex/OpenFUT/scripts/systemd/README.md
# PRODUCTION TEMPLATE — NOT INSTALLED.
Requires=openfut-netns.service
After=openfut-netns.service
Wants=openfut-core.service
After=openfut-core.service
# `Wants` on Core, deliberately NOT `Requires`/`BindsTo`/`PartOf` — measured on
# staging: those propagate a Core stop into a host stop, and a later Core start
# does NOT bring the host back, so a routine Core restart would leave the client
# with no server at all. With `Wants` the host survives a Core outage, answers
# 503 `core_unavailable` (never a Python fallback), and resumes serving the
# moment Core returns with no supervisor intervention. Both halves were proven
# on the staging units.
#
# `Requires` on the netns unit IS correct: without the namespace the host would
# bind the wrong network entirely.
# StartLimit* MUST live in [Unit]: systemd 252 silently IGNORES them in
# [Service] (`systemd-analyze verify` flags it), which would have left the
# crash-loop ceiling at the 10s/5 default instead of the intended 60s window.
StartLimitIntervalSec=60
StartLimitBurst=5
[Service]
Type=exec
User=root
NetworkNamespacePath=/run/netns/openfut
EnvironmentFile=/etc/openfut/host.env
# Admission gate. Ordering alone proves nothing about readiness (Type=exec only
# proves the binary exec'd). Core binds its port only after migrations and the
# content pack have loaded, so "port open" is a real readiness signal here.
# Bounded and FAILING rather than blocking: a host that waits forever looks
# healthy to the supervisor while serving nobody.
ExecStartPre=/home/alex/OpenFUT/scripts/systemd/openfut-wait-tcp.sh 127.0.0.1 18080 30
ExecStart=/home/alex/openfut-migration/promote-contract-20260822-184409/artifacts/openfut-utas-host
KillSignal=SIGTERM
KillMode=mixed
TimeoutStopSec=30
Restart=on-failure
RestartSec=5s
StandardOutput=journal
StandardError=journal
SyslogIdentifier=openfut-host
[Install]
WantedBy=multi-user.target
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#!/bin/sh
# Publish a Docker container's network namespace into /run/netns so systemd
# units can enter it declaratively with NetworkNamespacePath=.
#
# WHY THIS EXISTS. Production Core and host must run inside the
# `openfut-fut-backend` container's netns: that is where the published client
# ports live and where the Python oracle answers on 127.0.0.1:8199. Today they
# get there with `nsenter --net=/proc/<pid>/ns/net`, where <pid> is typed by
# hand into a runbook.
#
# THE HAZARD THIS FIXES, MEASURED NOT ASSUMED. The container runs with
# `restart=unless-stopped`. On a container restart its netns inode CHANGES
# (observed 2026-08-22: net:[4026539938] -> net:[4026540033]). A hardcoded pid
# is then simply wrong, and — worse — any process already inside the old
# namespace keeps running in a namespace with no interfaces, silently serving
# nobody. Resolving by container NAME at every start removes the hardcoded pid;
# the companion watcher unit handles the already-running case by restarting the
# stack when the container restarts.
#
# Idempotent: a stale bind mount is unmounted and re-made, so re-running after a
# container restart is the fix, not a second problem.
#
# usage: openfut-netns-bind.sh <container-name> <netns-name>
set -eu
CONTAINER="${1:?container name}"
NSNAME="${2:?netns name}"
TARGET="/run/netns/${NSNAME}"
CPID="$(docker inspect -f '{{.State.Pid}}' "$CONTAINER" 2>/dev/null || true)"
if [ -z "$CPID" ] || [ "$CPID" = "0" ]; then
echo "openfut-netns-bind: container '$CONTAINER' is not running (pid='$CPID')" >&2
exit 1
fi
if [ ! -e "/proc/$CPID/ns/net" ]; then
echo "openfut-netns-bind: /proc/$CPID/ns/net does not exist" >&2
exit 1
fi
WANT="$(readlink "/proc/$CPID/ns/net")"
mkdir -p /run/netns
# Already published and already CURRENT? Then do nothing — re-mounting under a
# live service would be gratuitous churn.
if mountpoint -q "$TARGET" 2>/dev/null; then
HAVE="ns:[$(stat -c %i "$TARGET" 2>/dev/null || echo 0)]"
if [ "net:[$(stat -c %i "$TARGET" 2>/dev/null)]" = "$WANT" ]; then
echo "openfut-netns-bind: $TARGET already current ($WANT)"
exit 0
fi
echo "openfut-netns-bind: $TARGET is STALE ($HAVE, want $WANT) — refreshing"
umount "$TARGET" || true
fi
[ -e "$TARGET" ] || touch "$TARGET"
mount --bind "/proc/$CPID/ns/net" "$TARGET"
echo "openfut-netns-bind: $TARGET -> $CONTAINER pid $CPID $WANT"
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[Unit]
Description=OpenFUT: publish the FIFA17 container network namespace to /run/netns
Documentation=file:///home/alex/OpenFUT/scripts/systemd/openfut-netns-bind.sh
# PRODUCTION TEMPLATE — NOT INSTALLED. Staging runs in the host netns and needs
# none of this; only production enters the `openfut-fut-backend` container's
# namespace.
After=docker.service
Requires=docker.service
[Service]
Type=oneshot
RemainAfterExit=yes
# Re-resolves the container by NAME on every start, so no pid is ever hardcoded
# and a container restart is repaired by restarting this unit. It exits non-zero
# when the container is not running, which is what makes Core's Requires= on it
# a real admission gate rather than decoration.
ExecStart=/home/alex/OpenFUT/scripts/systemd/openfut-netns-bind.sh openfut-fut-backend openfut
# Deliberately NO ExecStop unmount. Tearing the bind mount down while Core and
# the host are still inside that namespace would strand them; the namespace is
# owned by the container's lifetime, not by this unit's.
StandardOutput=journal
StandardError=journal
SyslogIdentifier=openfut-netns
[Install]
WantedBy=multi-user.target
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[Unit]
Description=OpenFUT Core (STAGING) — authoritative economy state
Documentation=file:///home/alex/OpenFUT/scripts/systemd/README.md
# Staging Core is the write authority for the staging SQLite DB. Nothing else
# may hold it open, which is why there is no second instance and no oneshot
# migration unit: Core runs its own migrations at startup, before it binds.
After=network-online.target
Wants=network-online.target
# StartLimit* MUST live in [Unit]: systemd 252 silently IGNORES them in
# [Service] (`systemd-analyze verify` flags it), which would have left the
# crash-loop ceiling at the 10s/5 default instead of the intended 60s window.
StartLimitIntervalSec=60
StartLimitBurst=5
[Service]
Type=exec
User=alex
Group=alex
WorkingDirectory=/home/alex/openfut-sold-staging
# Config is DATA, not baked into the unit, so the same unit file promotes to
# production with a different EnvironmentFile.
EnvironmentFile=/home/alex/openfut-sold-staging/systemd/core.env
# The binary is an IMMUTABLE COPY taken at staging-up time. A later `cargo
# build` cannot silently change what staging is running — the same property the
# promotion artifacts rely on.
ExecStart=/home/alex/openfut-sold-staging/bin/openfut-core
# Graceful stop. Both binaries already exit cleanly on SIGTERM (the
# restart-persistence harness has always stopped them that way), and 20s is far
# more than the observed sub-second shutdown; it exists so a slow WAL
# checkpoint is never SIGKILLed mid-write.
KillSignal=SIGTERM
KillMode=mixed
TimeoutStopSec=20
# Restart WITHOUT a tight loop. `on-failure` deliberately excludes a clean
# operator stop. 5s spacing with a 5-in-60s ceiling means a genuinely broken
# build lands in `failed` where it is visible, instead of thrashing the DB.
Restart=on-failure
RestartSec=5s
StandardOutput=journal
StandardError=journal
SyslogIdentifier=openfut-staging-core
[Install]
WantedBy=multi-user.target
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[Unit]
Description=OpenFUT FIFA17 UTAS host (STAGING) — client-facing, Core-dependent
Documentation=file:///home/alex/OpenFUT/scripts/systemd/README.md
# ORDERING AND ADMISSION. `Wants` + `After` order the host after Core and pull
# Core in when the host is started; neither gives READINESS, because Type=exec
# only proves the binary exec'd. The ExecStartPre below is what actually admits
# traffic: the host cannot reach "active" while Core is not listening.
Wants=openfut-staging-core.service
After=openfut-staging-core.service
# `Wants`, deliberately NOT `Requires`/`BindsTo`/`PartOf`. Those propagate a
# Core stop into a host stop, and — measured, not assumed — a later Core start
# does NOT bring the host back, so a routine Core restart would silently leave
# the client with no server at all.
#
# With `Wants` the host survives a Core outage and answers 503
# `core_unavailable`, never falling back to Python. That is the behaviour
# production already exhibited on 2026-08-22 when Core was SIGHUP'd out from
# under a live host. Because the host holds no Core state between requests, it
# resumes serving the moment Core returns, with no supervisor intervention.
# StartLimit* MUST live in [Unit]: systemd 252 silently IGNORES them in
# [Service] (`systemd-analyze verify` flags it), which would have left the
# crash-loop ceiling at the 10s/5 default instead of the intended 60s window.
StartLimitIntervalSec=60
StartLimitBurst=5
[Service]
Type=exec
User=alex
Group=alex
WorkingDirectory=/home/alex/openfut-sold-staging
EnvironmentFile=/home/alex/openfut-sold-staging/systemd/host.env
# Readiness gate. Bounded, and FAILS rather than blocking forever: a host that
# waits indefinitely looks healthy to the supervisor while serving nothing.
ExecStartPre=/home/alex/OpenFUT/scripts/systemd/openfut-wait-tcp.sh 127.0.0.1 18081 30
ExecStart=/home/alex/openfut-sold-staging/bin/openfut-utas-host
KillSignal=SIGTERM
KillMode=mixed
TimeoutStopSec=20
Restart=on-failure
RestartSec=5s
StandardOutput=journal
StandardError=journal
SyslogIdentifier=openfut-staging-host
[Install]
WantedBy=multi-user.target
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#!/bin/sh
# Bounded wait for a TCP listener. Exits 0 as soon as it connects, 1 on timeout.
#
# Used as the FIFA17 host's ExecStartPre so the host cannot start "successfully"
# while Core is absent. A TCP connect is a MEANINGFUL readiness signal here, not
# a guess: openfut-core binds its listener only after it has opened the
# database, run migrations and loaded the content pack — the startup log order
# is `Running database migrations` -> `Loaded N cards` -> `Listening`, and the
# 2026-08-22 promotion demonstrated it directly when a bind collision aborted a
# Core that had already applied migration 0028. So "port open" implies
# "migrations done, content loaded".
#
# Deliberately no retry-forever: a host that blocks indefinitely looks healthy
# to a supervisor while serving nothing. It fails, and the restart policy
# decides what happens next.
#
# usage: openfut-wait-tcp.sh <host> <port> <timeout-seconds>
set -eu
HOST="${1:?host}"
PORT="${2:?port}"
TIMEOUT="${3:-30}"
i=0
while [ "$i" -lt "$TIMEOUT" ]; do
# /dev/tcp is a bash-ism; use a portable connect instead.
if command -v nc >/dev/null 2>&1; then
nc -z "$HOST" "$PORT" 2>/dev/null && exit 0
else
python3 - "$HOST" "$PORT" <<'PY' && exit 0
import socket, sys
s = socket.socket()
s.settimeout(1)
sys.exit(0 if s.connect_ex((sys.argv[1], int(sys.argv[2]))) == 0 else 1)
PY
fi
i=$((i + 1))
sleep 1
done
echo "openfut-wait-tcp: $HOST:$PORT did not accept connections within ${TIMEOUT}s" >&2
exit 1