Backups
Poindexter backs up its Postgres state in tiers. Tier 1 ships in the default Docker stack —docker compose up and you’re protected against
accidental drops, migration mishaps, and container wipes. Tier 2 is
opt-in for off-machine durability (drive failure, theft, ransomware).
Tier 1 — in-stack hourly + daily dumps
Two compose services, one tiny image (scripts/Dockerfile.backup):
Both write
pg_dump --format=custom into a bind-mounted host
directory (NOT a docker named volume). Bind mounts survive
docker volume prune and Docker Desktop reinstalls — the failure mode
that lost a day of state on 2026-05-05 and prompted this work.
Each tier reads its config from app_settings at every tick — no
container restart needed when you tune cadence or retention:
Override the host directory by setting
POINDEXTER_BACKUP_DIR
(e.g. to a second drive) before docker compose up.
Restore
Tier 2 — off-machine (optional, recommended)
Same-drive backups don’t survive drive failure, theft, or ransomware. Tier 2 streams a fresh, encrypted copy of the database off-machine to any S3-compatible bucket (Backblaze B2, AWS S3, Cloudflare R2, MinIO) via restic — encrypted, deduplicated, retention-managed. At our scale it runs ~0.005/GB/mo on B2).Setup wizard
- Append-only key check (advisory) — probes whether the S3 key can
DeleteObject. An append-only key (one that cannot delete) is strongly recommended: a ransomed host can then write new snapshots but cannot destroy backup history. If the key is delete-capable the wizard warns and asks for explicit confirmation. restic init— creates the encrypted repo.- First backup (acceptance gate) — streams a fresh
pg_dump -Z0 | restic backup --stdin(the same shape the runner uses below), so this first snapshot shares the runner’s(host, stdin-filename)parent key and the runner’s very first tick dedupes against it instead of re-ingesting the whole dump. If thepoindexter-backupimage or the postgres network isn’t available it falls back to a pinned-resticbackup of the latest daily dump. Either way, if this fails nothing is persisted — you fix the problem and re-run. - Encrypted persist — writes the repo URL (plaintext) and the restic
password + S3 key pair (encrypted via pgcrypto) to
app_settings, then prints the restic password once for you to save offline.
⚠️ Save the restic password offline — now
The wizard generates a high-entropy restic repository password and stores it encrypted inapp_settings. In a drive-failure / theft / ransomware event the database and this machine are gone, so a copy that lives only in the DB is no copy at all. Write the printed password to your password manager / a fireproof safe. Without it the remote repo is unrecoverable — restic encryption with a lost password is final.
The backup-offsite runner
poindexter backup setup configures an in-stack backup-offsite compose
service (alpine + restic, reusing scripts/Dockerfile.backup). On its cron
it:
- streams a fresh uncompressed
pg_dump --format=custom -Z0straight intorestic backup --stdin, stamping anaudit_logheartbeat (offsite_backup_succeeded) on success; - backs up the config surface as a second snapshot in the same repo
(
--tag config), stampingoffsite_config_backup_succeeded; - once a week runs
restic check --read-data-subset=<pct>%against the remote to catch bit-rot, stampingoffsite_backup_verified.
Why the config snapshot exists (poindexter#889). Until 2026-08-27 this runner shipped exactly one thing — apg_dump. Everything else that is irreplaceable rode only on the Tier 3 DR USB job:~/.poindexter(whosebootstrap.tomlholdspoindexter_secret_key) and~/.claude(the memory tree). When that USB drive was removed, every copy of the secret key collapsed onto a single partition — and #889 is exactly the trap that springs then: lose that key and the encryptedapp_settingsrows holding this repo’s own restic password and S3 credentials cannot be decrypted, so the healthy DB snapshot becomes unopenable. The config snapshot closes the partial-loss case (disk dies, credentials survive off-machine). It does not by itself break the #889 cycle — opening the repo still requires the restic password held out-of-band, so Store the offsite credentials OFF the machine remains mandatory, not optional. restic encrypts at rest, so shipping secret-bearing config here is defensible; it is the same content the USB tier already carried. The compose files bind~/.poindexter→/config/poindexterand~/.claude→/config/claude, both read-only. The runner excludes the derived bulk (Tier 1 dumps, rendered video/images, the deploy clone, venvs, logs). A configured path that isn’t mounted is skipped with a warning; all paths missing raises awarningalert rather than reporting an empty success. A config-backup failure is warning-level and non-fatal — the DB snapshot has already succeeded by then, so prune/verify still run. Whybackup-offsiteruns as a different user than its siblings. The config surface is0700/0600owned by the host user, so the image’s built-in uid cannot even traverse it.backup-offsitetherefore carriesuser: "${POINDEXTER_HOST_UID:-1000}:${POINDEXTER_HOST_GID:-1000}", andstart-stack.shderives those fromid -u/id -gso they are correct on any host rather than correct by coincidence (pin them explicitly withpoindexter_host_uid/_gidinbootstrap.tomlif you need to — an already-set value always wins).backup-hourly/backup-dailydeliberately keep the image uid: theirhourly/anddaily/dump directories are owned by it, so rebuilding the shared image with a differentHOST_UIDwould break Tier 1 writes. Because the host uid cannot write the image’s/var/cache/restic, this service also setsRESTIC_CACHE_DIR=/tmp/restic-cache— a per-run index optimisation, not state. Get this wrong and the runner says so: a mounted-but-unreadable path raises awarningalert and is never handed to restic. That guard matters because restic exits 3 on unreadable content but still SAVES A SNAPSHOT (processed 0 files ... snapshot saved, verified on 0.16.4) — sorestic snapshots --tag configwould otherwise list reassuring entries containing nothing. Verify this backup withrestic ls, never by snapshot existence or exit code. Measured payload (2026-08-27), and the knob to turn if B2 grows:The~/.claudefigure is ~329 MB of session transcripts underprojects/; the genuinely irreplaceable part (thememory/trees) is 2.7 MB. Transcripts are write-once, so restic dedupes them and each later snapshot adds only new files — butoffsite_backup_prune_enableddefaults tofalse(append-only posture), so that lineage grows without bound. B2’s free tier is 10 GB and has been breached once before (2026-07-16). If the repo approaches the cap, the cheapest trim is adding/config/claude/projectstooffsite_backup_config_excludes— a single-row settings change, no deploy — which keepssettings.json, plugins, and agent memory while dropping the transcript bulk. Note this also drops the per-projectmemory/trees, so pair it with a separate backup of those if you take it.
Why an uncompressed dump, notrestic backupof the Tier 1 files? Tier 1 writespg_dump --format=custom(zlib-compressed). restic dedupes and compresses via content-defined chunking, and compressed bytes defeat both — a one-row change reshuffles the whole compressed stream, so every daily dump reads as 100% new data. Measured 2026-07-11: 1.01× restic compression, ~150–230 MiB added per dump, repo at 8.3 GiB across 62 snapshots after 25 days (append-only, never pruned) — on track to breach B2’s 10 GB free cap in ~1–2 weeks. Feeding restic an uncompressed dump lets it dedupe the ~unchanged bulk day-over-day and compress its own packs, so the repo holds near the live DB size (~1 GB) regardless of snapshot count. The runner takes its own dump (it already has psql/pg_dump connectivity) rather than re-reading Tier 1’s files, so Tier 1’s dumps, retention, and restore-test are left untouched.set -o pipefailsurfaces a mid-streampg_dumpfailure even if restic exits 0 on the truncated input, so a half-streamed dump alerts instead of saving a short snapshot. This change slows growth going forward; it does not shrink the existing repo. To reclaim space already stored under the old scheme, prune once (see below) or start a fresh repo path.
start-stack.sh decrypts the three secrets into a git-ignored
.poindexter-backup-offsite.env on every up/restart, so the runner picks
up credentials without any .env you maintain by hand.
Append-only posture (ransomware resilience)
The runner is backup-only — it never issuesrestic forget/prune
(which delete objects), so a write-only S3 key (no deleteFiles) is
sufficient and is the recommended configuration. With the streamed
uncompressed dump above, per-snapshot growth is a small delta, so the
append-only repo stays under B2’s free cap for a long time without any
pruning at all.
Do NOT bound a restic repo with a raw age-based bucket lifecycle rule.
restic stores data in immutable pack files that stay referenced by future
snapshots indefinitely; a “delete objects older than N days” lifecycle rule
deletes live packs and corrupts the repo. The only safe way to reclaim
space is restic’s own forget --prune, which needs a delete-capable key —
enable it via the offsite_backup_prune_enabled escape hatch (default
false). To keep the ransomware guarantee while using a delete-capable key,
put the bucket under Object Lock / WORM (a compliance-mode retention
window bounds how long a compromised host could hold deletion off), or run
the prune from a separate trusted context. See the B2 reclaim steps in the
2026-07 offsite-dedup PR for the recommended one-time cleanup.
Before relying on forget --prune to reclaim space, confirm the bucket
has a version-expiry lifecycle rule — a different setting from the
age-based rule warned against above. forget --prune’s deletes only hide
the current version of an object; B2 keeps every prior version of every
object indefinitely unless told otherwise, so without a rule expiring
hidden/previous versions, the “reclaimed” space stays fully billed and fully
counted against the Daily Storage Cap. (Confirmed 2026-07-16: a prune took
restic’s own view from 62 snapshots/8.3 GiB down to 16/1.8 GiB, but B2’s
reported usage stayed at 10.1 GB — the whole gap was retained hidden
versions.) Set the bucket’s file-lifecycle setting to “Keep only the last
version of the file” — this only purges already-hidden versions and never
touches a live/current object, so it’s safe to apply even with snapshots
still referencing other files in the same bucket.
Operator commands
⚠️ Store the offsite credentials OFF the machine
A backup you cannot open is not a backup. The offsite repository’s credentials are stored as encryptedapp_settings rows
(offsite_backup_restic_password, offsite_backup_s3_access_key_id,
offsite_backup_s3_secret_access_key) — that is, inside the database the
backup contains — and the key that decrypts them (poindexter_secret_key)
lives only in ~/.poindexter/bootstrap.toml, which the runner does not back
up. The runner streams exactly one pg_dump and nothing else.
So after a total loss the only surviving artifact is the restic repository, and
opening it requires three values that existed only on the machine you lost:
This is easy to miss because every signal stays green:
backup run succeeds,
snapshots are created and retained, and backup verify passes. Those prove the
repo is writable and intact — never that it is reachable without this
machine.
Copy the restic password, the S3 key pair, and the repository URL into a
password manager (or print them) the day you run backup setup.
Recovery drill — prove you can actually get back in
verify-recovery reads nothing from this install — not the database, not
bootstrap.toml, not app_settings. You supply the credentials you keep
off-machine and it lists the snapshots they can open. Any option you omit is
prompted for with hidden input, so nothing lands in shell history.
A pass means the recovery path is real. A failure means you have just found out
your backup is unrecoverable while you still have a working machine to fix it
from — which is the entire point of running it. Run it from a different machine
for a true drill; running it here still proves the credentials are correct and
complete, which is the part that actually gets missed.
Re-run it after any credential rotation, and periodically regardless — a backup
is only proven by a recovery drill performed without access to the source
machine.
Settings (app_settings)
All Tier 2 tunables are DB-backed (seeded every boot, so they reach
existing deployments — only the three secrets are written by the wizard):
The three secrets —
offsite_backup_restic_password,
offsite_backup_s3_access_key_id, offsite_backup_s3_secret_access_key —
are is_secret=true (pgcrypto-encrypted) and are written by the wizard, not
seeded.
Brain offsite-backup watch (auto-retry before paging)
brain/offsite_backup_watch.py (poindexter#386) is the self-heal layer for
the offsite tier — a sibling of backup_watcher with one difference: its
freshness source is the audit_log heartbeat (offsite_backup_succeeded), a
creds-free DB read, so the brain never touches the restic password. Each
cycle it reads the heartbeat age; if it’s past offsite_backup_max_age_hours
it docker restarts poindexter-backup-offsite, waits, and re-reads. After
offsite_backup_watch_max_retries cumulative failures it emits a firing
offsite_backup_stale alert (critical) and stops kicking. Unlike
backup_watcher — which leans on the runner’s own failure alert plus the
Tier 1 healthcheck — the offsite tier has no other alert source for a dead
runner, so this watch emits its own firing alert on escalate.
Restore from the remote
When the machine is gone, restore from the remote repo with the offline restic password — see the DB-4 runbook indisaster-recovery.md.
Failure handling
The runner inserts a row intoalert_events (severity=critical) on
any non-zero exit. The brain daemon’s alert_dispatcher poll picks it
up on its 30s sweep and routes through the same Telegram (critical) +
Discord (warning) pipeline Grafana alerts use — one notification surface,
not three. The alert description includes a truncated tail of restic’s
actual stderr, not just the exit code, so the real cause (credentials,
network, a B2 cap) doesn’t require digging through docker logs poindexter-backup-offsite to find. A subsequent successful backup
auto-resolves the firing row via brain/offsite_backup_watch.py’s
fresh-heartbeat check, the same way it already resolves offsite_backup_stale.
If the failure is “postgres is unreachable”, the alert insert itself
will fail (chicken-and-egg). The container’s healthcheck catches that
case: it flips to unhealthy if the latest hourly dump is > 90 minutes
old, which Grafana surfaces directly via the standard container-down
alert path.
Brain backup-watcher (auto-retry before paging)
brain/backup_watcher.py (Glad-Labs/poindexter#388) sits between a
backup failure and the operator’s phone. Every cycle it stats the
newest dump in each tier; if either is past its threshold it
docker restarts the relevant container, waits the configured delay,
and re-stats. When a fresh dump appears it writes a
status='resolved' row to alert_events so the dispatcher pages the
operator with [RESOLVED · ...] instead of leaving them wondering. If
the retry budget is exhausted without recovery, the watcher backs off
and lets the original firing alert stand — the operator still gets
paged, just on the actual problem rather than on a transient hiccup.
dr-backup sentinel surfacing (#444)
The host-side dr-backup scripts at~/.poindexter/scripts/dr-backup/
write a dr-backup-*-failed.sentinel file under ~/.poindexter/logs/
when both:
- the script itself failed (non-zero exit), AND
- the script’s primary Telegram alert path failed too (creds missing, postgres down, network broken).
brain/backup_watcher.py scans the configured backup_watcher_sentinel_dir
each cycle and inserts a firing alert_events row for every sentinel it
finds, named dr_backup_hourly_failed or dr_backup_daily_failed. The
fingerprint embeds the sentinel’s ts field so re-scans of the same
sentinel dedup — the operator gets exactly one page per failure
incident, not one per probe cycle. Cleanup is owned by the script side
(it rms its own sentinel on the next successful run), so brain never
deletes files it didn’t write.
The bind mount ~/.poindexter/logs:/host-backup-logs:ro in
docker-compose.local.yml (under the brain-daemon service) is what
exposes the sentinel directory inside the container. If you change
backup_watcher_sentinel_dir, change the mount target to match.
⚠️ The sentinel only covers script failures, not the script never running. A sentinel is written by the dr-backup script, so anything that stops the script from starting is invisible to this path. The systemd units carryRequiresMountsFor=/mnt/dr-usb, and the fstab entry carriesnofail— so with the USB drive absent the unit fails at the dependency level, the script never executes, no sentinel is written, and the brain sees nothing at all. This is not hypothetical: it hid a dead Tier 3 for at least a week in August 2026, visible only as hourlyDependency failedlines injournalctl. If you rely on Tier 3, monitor the timer, not just the sentinel.
Tier 3 (DR USB) — PARKED 2026-08-27
The DR USB timers are deliberately disabled, not broken: the stick was failing and was removed pending a replacement drive.systemctl list-timers
will not show them, and that is the expected state — do not page on it.
/etc/systemd/system/, so re-arming on the
replacement drive is one command (after adding the new UUID to /etc/fstab
at /mnt/dr-usb):
~/.poindexter
and ~/.claude until the Tier 2 config snapshot above was added on the same
day. With that in place, the config surface is still backed up off-machine
daily — but Tier 3 remains the only local, offline copy, and offline is the
tier that survives a credential compromise or an account lockout. Treat the
replacement drive as owed work, not optional.
Restore test (does the dump actually restore?)
brain/restore_test_probe.py (Glad-Labs/poindexter#441) is the layer that
proves a dump restores, not just that it’s fresh. Once per
restore_test_interval_hours (default 24h) the brain picks the newest dump
under /host-backups/auto/daily/, spins a throwaway pgvector/pgvector:pg16
container, pg_restores the dump, re-runs the production migration runner
against it (migrations_smoke.py, via docker exec into the worker), asserts
the critical tables (posts, app_settings, audit_log) survived with rows
and schema_migrations is populated, then tears the throwaway down.
A verification failure (corrupt dump, empty table, smoke failure) pages at
error — “your latest backup may be corrupt”. An infra failure (docker
unreachable, no dump found) is warning — Discord only, so a transient hiccup
that merely prevented the test doesn’t train you to ignore Telegram. State
(last-run time) lives in audit_log, so a brain restart doesn’t re-trigger the
heavy run. No new compose mounts — it reuses the docker socket and the
read-only /host-backups mount already wired for the backup-watcher.
Operational hygiene
- Disk: 24h × 128 MB ≈ 3 GB hourly + 7d × 128 MB ≈ 900 MB daily.
Total ~4 GB at our current scale; multiply by your
poststable growth. - Healthcheck cadence: hourly tier is checked every 5 min; daily every 30 min. Both with 90-min staleness slack to avoid flapping during the legitimate gap between tick and rotation.
- Logs land in Docker’s container log (visible via
docker logs poindexter-backup-hourly). Promtail ships them to Loki for Grafana queries.
Future
- poindexter#387: brain daemon SMART monitoring — surface drive-failing-soon warnings before drives actually die.
- USB / external-drive Tier 2 backend (deferred from #386 — the Windows drive-letter→container mount needs its own design pass).
- A Grafana panel for the offsite tier (the
audit_logoffsite_backup_succeeded/offsite_backup_verifiedevents make it queryable today).