# ks4 pull leg — seed after FTTH

Status: **prepared, waiting on the FTTH link.**

⚠️ **Changed 2026-08-30: this leg lands on `nas`, not on nuc.** It was
originally designed for nuc's USB pool `usb4t`, but that pool proved to
be the least reliable device in the setup
([nuc/usb4t-dropouts.md](../nuc/usb4t-dropouts.md)) — which is exactly
what an off-site copy of ks4 must not be. The 4 TB disk moved to direct
SATA on the new host `nas` (`192.168.0.4`,
[nas/nas-install.md](../nas/nas-install.md)), and the target pool
`ks4backup` moved with it.

Consequences versus the original plan:

- Target pool `ks4backup` is now backed by `tank/backup/ks4` on nas.
- The **WireGuard tunnel moves too**: nas becomes peer `10.8.0.22`.
  `transmission-bt`, the only other user, moved to nas and carries its
  own in-container tunnel (`10.8.0.21`, unchanged — ks4 needs no edit
  for it).
- ⚠️ **nuc's `wg-ks4` was already disabled on 2026-08-31**, *before* the
  seed, not after. The original plan retired it only once nas was
  seeded, on the assumption nuc could serve as a fallback target — it
  cannot: its `ks4backup` pool was deleted and its `data` pool is a
  512 GB SSD, far too small for the ~1.75 TiB replica set. Keeping a
  keepalive'd tunnel alive on a machine that is now powered off between
  uses bought nothing. `wg-quick@wg-ks4` is `disabled`, and the `ks4`
  incus remote was removed from nuc.
  `/etc/wireguard/wg-ks4.conf` and its key are **kept**, so it is one
  `systemctl enable --now wg-quick@wg-ks4` away if ever needed.
- ks4's ufw rule is unchanged: traffic arrives masqueraded as the
  `wireguard` container (`192.168.1.18`) whichever peer sent it.

## Prerequisites

- [ ] `tank` running on SATA for ≥ 7 days with zero pool suspensions —
      the gate that replaces "fix the USB enclosure"
- [ ] FTTH up (the first pass moves ~1.75 TiB)

## Setup (root on nas)

```sh
# 1. peer nas on ks4's wireguard container
#    (run on ks4) — <nas-pubkey> from /etc/wireguard/wg-ks4.key on nas
incus exec wireguard -- wg set wg0 peer <nas-pubkey> allowed-ips 10.8.0.22/32
incus exec wireguard -- wg-quick save wg0

# 2. tunnel on nas: /etc/wireguard/wg-ks4.conf, modelled on nuc's
#    Address = 10.8.0.22/32, peer pubkey TVs6d7…,
#    Endpoint = 193.70.35.17:51845,
#    AllowedIPs = 10.8.0.0/24, 192.168.1.1/32, keepalive 25
systemctl enable --now wg-quick@wg-ks4

# 3. incus remote over the tunnel
incus remote add ks4 https://192.168.1.1:8443 --accept-certificate --token '…'
incus list ks4: | head          # sanity: remote reachable
```

## Seed

```sh
# full pull of every ks4 instance into pool ks4backup (tmux — first pass
# moves ~1.75 TiB through the WG tunnel)
/root/scripts/incus-copy.sh -r ks4 -s ks4backup 2>&1 | tee -a /var/log/incus-copy-ks4.log
```

Notes:

- First pass is a full send per instance; later refreshes are
  ZFS-incremental **as long as they run at least every
  `snapshots.expiry` (7 d on ks4)** — same caveat as
  [ks4's local leg](../ks4/local-backup-cron.md).
- Replicas arrive stopped with `boot.autostart=false` (the script does
  this) — they must never come up on the LAN with ks4's proxy devices.

## Cron (after the seed)

Add to nas's root crontab, offset from the 03:30 nuc→nas push, the
04:00 nas→nuc push and ks4's own 01:00/05:00 jobs:

```cron
0 5 * * * /root/scripts/incus-copy.sh -r ks4 -s ks4backup >> /var/log/incus-copy-ks4.log 2>&1
```

## Verification (release gate for ks2)

```sh
incus list --project backup -c ns -f csv         # all ks4 instances present
# test-restore one instance: copy a replica to the local pool,
# start it isolated, check the service answers, then delete it
incus copy solar solar-restoretest -s incus
incus start solar-restoretest && incus exec solar-restoretest -- systemctl is-system-running
incus delete -f solar-restoretest
```

Once verified, tick the nas gate in the [ks2 plan](plan.md).

Only one piece of nuc's retirement is still outstanding — dropping its
now-unused peer on ks4. Harmless to leave (an unused peer costs nothing)
and safe to do at any time, since nuc's tunnel is already down:

```sh
# on ks4 — nuc's pubkey is 31Tlgloc…
incus exec wireguard -- wg set wg0 peer 31TlglocNJyooDVAO8HWEC0lyCykhbaFIWVWFUCOrmQ= remove
incus exec wireguard -- wg-quick save wg0
```

Deleting `/etc/wireguard/wg-ks4.conf` + `.key` on nuc is deliberately
**not** done: they cost nothing and regenerating keys would mean
re-peering on ks4.