# ks2 decommission — summary plan

Goal: release `ks2.lutran.fr` (`164.132.173.57`, SSH :2233, host
`ns3247221`) once ks4 has a real 3-2-1 backup without it.
**Deadline: rental ends Sep 30, 2026.**

## What ks2 does today (updated 2026-08-22)

One remaining role, fed nightly by a root cron **on ks4**:

- `04:00` `incus-backup.sh … -d 164.132.173.57` — DB dumps + selected
  paths rsync'd to ks2 `/backup/ns3061243` on pool `backup` (1.59 T,
  88 % full), snapshotted daily on ks2 (`zfs-auto-snapshot.sh`,
  2-month expiry). **Kept as a stopgap** until the plakar S3 leg
  replaces it.

Retired: the `01:00` replica push to ks2 pool `data` — replaced by
the local leg on ks4's sdb5 pool
([local-backup-cron.md](../ks4/local-backup-cron.md)); `biwiki` and `spot`
deleted from ks2.

## Inventory findings (2026-08-22)

- `biwiki` exists only on ks2, `spot` only on ks2 + ks4's `backup`
  project — **decision: both abandoned**, safe to delete from backups.
- `incus-backup.db` is stale (lists `spot`, misses `livetrail`,
  `outline`, `login`, …) — forgotten-manifest drift is exactly what
  the plakar-based replacement must eliminate (back up *all*
  instances by default, opt-out instead of opt-in).
- `livetrail` (running on ks4) is **absent from ks4's local `backup`
  project** — the local leg was run manually once and never again;
  automating its cron fixes this.
- Both ks4 backup crons were **commented out — no ks4 backup ran at
  all** (hence the stale ks2 rsync data: dirs `Jul 23`, incus dumps
  `Aug 9`). Fixed 2026-08-22 — see
  [local-backup-cron.md](../ks4/local-backup-cron.md).
- `/backup/ns3061243` also holds pre-2023 dirs (`catc`, `mythoughts`,
  `qcm`) — those instances still exist stopped on ks4, so nothing
  unique expected there; spot-check before wiping.
- Losing ks2 also loses its 2 months of rsync-snapshot history —
  acceptable once plakar has built equivalent retention.

## Target architecture (3-2-1 for ks4)

| Leg | Mechanism | Status |
|---|---|---|
| local, 2nd disk | `incus-copy.sh -p backup -s backup` → sdb5 pool | works, **cron missing** |
| off-site, nuc | nuc pulls `ks4:*` → pool `ks4backup` over WG | waiting FTTH seed |
| off-site, S3 (data+DB) | **restic** on ks4 → S3 (plakar ran it first, being replaced — see [restic-backup.md](../ks4/restic-backup.md)) | migrating |
| off-site, S3 (instances) | restic over `incus file mount` of the `backup`-project replicas | designed |
| off-site, ks2 (interim) | 02:00 replica push until the nuc leg seeds (FTTH < Sep 30) | to re-enable |

## Actions (backup work documented in [`../ks4/`](../ks4/), ks2-only tasks here)

1. ~~salvage biwiki/spot~~ — decided 2026-08-22: both abandoned,
   **deleted** from ks2 and ks4's `backup` project
2. ~~[local-backup-cron.md](../ks4/local-backup-cron.md)~~ — **done
   2026-08-22**: leg 1 cron re-enabled, ks2 rsync kept as stopgap;
   `livetrail` verified present in the `backup` project
3. [plakar-s3-data.md](../ks4/plakar-s3-data.md) — **seeding S3
   2026-08-22** (direct-to-S3 kloset `lutran-ks4-plakar-data`, driver
   script `scripts/plakar-backup.sh`, pipeline validated locally);
   next: restore test + cron
4. [plakar-incus-integration.md](../ks4/plakar-incus-integration.md) —
   design seeded 2026-08-22: per-file importer over the incus sftp
   API, instances → S3
5. [nuc-seed.md](nuc-seed.md) — **prepared**; after FTTH: seed nuc
   pull leg, verify all instances, test-restore one
6. [decommission.md](decommission.md) — **prepared**; cut flows,
   final diff of `/backup/ns3061243`, wipe pools, terminate at OVH

## Release gates — ks2 can be dropped only when

- [x] biwiki + spot consciously abandoned (2026-08-22)
- [ ] local leg cron running ≥ a few days, all instances present
- [ ] nuc leg fully seeded **and** one instance test-restored
- [ ] plakar S3 data/DB backups running daily **and** one DB + one
      file tree test-restored
- [ ] ks4 crons pointing at ks2 disabled