Observed live: three redundant local backups on demo-felhom in one afternoon of
deploys. The backup Store is in-memory ('lost on restart; the cadence
re-populates'), so after every restart /backup/due said 'no successful backup
recorded yet' and the controller took another one. On the offsite tier that is a
wasted multi-hour WAN upload after every agent deploy.
- BackupRunner.NewestArchiveTime: when a backup last LANDED on this tier's
storage, read from the storage.
- localapi.BackupArchiveLister (optional BackupService extension): the due-check
takes whichever is newer, the in-memory record or the storage.
Asking the storage rather than persisting the store is deliberate: it is ground
truth (a pruned archive correctly stops counting, where a persisted record would
keep claiming a backup that no longer exists), needs no new on-disk state, and
answers only 'when did a backup last land' — the richer fields stay with real
records so the host-report never carries invented numbers.
Fail-safes: read error -> fall back to memory (never fake freshness, never
suppress); genuinely empty -> due; old archive -> still due; service without the
lister -> unchanged.
Red-proof observed; full suite green (29 packages).
v0.102.0 defers a tier whose target storage is absent. The Slice A harness used
fakeStorage{} with NO targets, so after that change it deferred every tier and
five Slice A assertions became vacuous failures.
The product behaviour is correct; the harness never modelled a real box, which
has both storages present. Fixed by giving it local + felhom-pbs.
My error, and worth naming: I ran the suite and committed in the same command,
read 'packages ok: 28' and pushed without checking rc=1. That is exactly the
exit-code trap recorded in this arc twice already.
Full agent suite green: rc=0, 29 packages.
Prerequisite for the installer default (host-install 1.20.0). A fresh box now
carries the offsite tier, but felhom-pbs only exists once the hub provisions the
DR tier. Without this the tier would report due in that window and the
controller would quiesce the apps and fire a vzdump at a missing storage every
cadence.
- GET /backup/due?target= defers when the target storage is absent
(targetStoragePresent): due:false with a reason that says why. The tier goes
live with NO restart once the storage appears.
Fail-safe: a storage-view ERROR returns present and the tier stays due. 'I could
not check' must never be read as 'not there' — that would silently suppress
backups, the absence-is-not-failure rule relearned three times now (R-80, R-81,
the R-82 wait timeout).
Full suite green.
Ruling 1 (2 weeks of weekly offsite backups): localPruneSpec's blanket PBS
refusal is now scoped — an ADDITIONAL tier with an explicit keep_last may
prune its PBS target. The refusal still applies in full to the PRIMARY tier,
because BackupTarget() defaults to felhom-pbs and KeepLast() defaults to 3, so
a box with neither key set would silently prune its offsite DR to 3 restore
points. An additional tier cannot have that accident (keep_last defaults to 0).
Ruling 3 (first backup runs as long as needed; nothing else starts until done):
- additional-tier wait bound 6h -> 12h (measured ~33 MB/min => ~5h for a first
full 10 GB snapshot; 12h gives margin but stays bounded so a hung task still
surfaces)
- ONE BACKUP AT A TIME PER GUEST across all tiers: POST /backup returns 409
when a DIFFERENT tier is in flight, naming the busy tier, with NO data object
so nothing is parseable as the caller's own job. Same tier still returns that
job (202, unchanged).
- snapshotted now counts as in-flight, not just running — after the snapshot the
vzdump is still uploading and holding the lock. The old check left a window
where a second POST started a real second vzdump. Latent bug, closed.
Full suite green (29 packages); red-proof observed and restored.
Mechanism only. No box changes behaviour until a backup_targets entry is
added to its config (Slice D); an untouched config resolves to exactly one
tier and behaves byte-identically to v0.96.0.
- config: BackupTargetConfig + ExtraTargets + BackupTiers(); each tier carries
its OWN cadence and retention (keep-last=3 is three days on a daily tier and
three weeks on a weekly one). A missing cadence is REJECTED, not defaulted —
a weekly DR tier silently running daily would fill the 37.2 GB datastore.
main.go logs every rejection at ERROR.
- /backup/due?target= judges a tier against its OWN newest successful backup.
Without that filter a fresh local backup satisfies the weekly PBS cadence and
the DR tier never runs — today's bug, re-created in code.
- GET /backup/tiers advertises the tiers; a 404 is the controller's pre-R-82
capability probe (Slice B).
- Jobs keyed by (vmid,target): single-flight is per tier, which is what lets
the weekly night run both backups in ONE quiesce window. Job ids are unique
per tier by construction, not by clock luck.
- One runner per tier: the runner holds target+retention as immutable state,
so parameterising one runner would risk pairing tier A's target with tier B's
retention.
COMPATIBILITY (frozen): untargeted /backup/due, POST /backup and
/backup/status keep the primary tier and the pre-R-82 response BYTES —
Target is omitempty and stays empty. The primary's job-id format is unchanged.
NOT changed: the local tier; PBS is still never pruned by the per-run flag
(keep_last defaults to 0 = never prune — enabling DR pruning is irreversible
and needs an operator ruling).
Tests 748->768. Red-proof #1 observed and restored.
Phase 0: felhom.eu/documentation/audits/SPIKE-r82-phase0-2026-07-26.md
admin
Claude Code