4 changed files with 11 additions and 980 deletions
--- a/infrastructure/CP1_UPDATE_PROCEDURE.md
+++ b/infrastructure/CP1_UPDATE_PROCEDURE.md
@ -1,382 +0,0 @@
-# k3s-cp-1 OS Update Procedure
-
-**Purpose:** apply the weekly Ubuntu OS updates to `k3s-cp-1`, the **sole** control-plane node of the k3s cluster, without triggering the kine/SQLite thundering-herd cascade documented in [DEV-495](/DEV/issues/DEV-495) and without losing api-server access longer than a normal reboot.
-
-**Audience:** the CTO agent, or an operator with root SSH to the cluster. Execution is board-approval-gated — see `## Approval gates` below.
-
-**Why cp-1 is not covered by the standard [`OS_UPDATE_PROCEDURE.md`](OS_UPDATE_PROCEDURE.md):**
-
- cp-1 has 3.7 GiB RAM and **zero swap** — during the 2026-08-16 worker-3 drain, `MemAvailable` dropped to 43 MiB while kine backed up on writes. cp-1's own drain evicts **more** state at once than any worker drain.
- cp-1 currently hosts 5 StatefulSets (`harbor-database`, `harbor-redis`, `nextcloud-redis-replicas`, `stalwart`, `stalwart-postgres`) plus 8 single-replica Deployments — all backed by Hetzner-CSI RWO volumes pinned to the fsn1 datacenter. A one-shot `kubectl drain` reschedules >13 pods simultaneously → guaranteed kine cascade.
- Rebooting cp-1 removes the entire kube-apiserver for the reboot window (~90–180 s expected). There is no fallback control-plane.
-
-The four kine thundering-herd guardrails from [`OS_UPDATE_PROCEDURE.md`](OS_UPDATE_PROCEDURE.md) still apply here. This procedure implements them for cp-1.
-
---
-
-## Scope
-
-**In scope**
-
- Add a durable ≥ 2 GiB swapfile on cp-1 (idempotent one-off — `--add-swap`).
- Pre-drain redistribution of stateful pods off cp-1, one at a time.
- k3s SQLite datastore snapshot as the restore point.
- `apt-get update/upgrade/dist-upgrade/autoremove` on cp-1.
- Controlled reboot with external liveness monitoring.
- Uncordon + cluster health verify.
-
-**Out of scope — do NOT do here**
-
- Any change to `/etc/rancher/k3s/*`, `/etc/systemd/system/k3s*.service*`, or the k3s binary version. k3s upgrades go through system-upgrade-controller (see `K3S_OPERATIONS.md`).
- Any change to manifests under `apps/`, `infrastructure/`, or applied via ArgoCD.
- Deleting PVs / PVCs. StatefulSets that get rescheduled off cp-1 stay on their new node — do NOT try to move them back.
- Fixing application-level problems ("harbor-core is CrashLoopBackOff after apt") — that's an app problem, escalate.
- Rebuilding the node. If cp-1 does not return after reboot, escalate; the rebuild path is `ADD_WORKER_NODE.md` plus board approval, not this document.
-
---
-
-## Approval gates
-
-This document has **two** independent gates. Neither happens without explicit board approval on the corresponding Paperclip issue:
-
-1. **Add swap (Phase A).** Non-invasive, non-state-mutating, kubelet already runs with `failSwapOn=false`. Requires board approval because it modifies the CP node.
-2. **Full OS update (Phases B–F).** Requires board approval because it drains cp-1 and reboots the sole api-server. Do NOT execute without an explicit `request_board_approval` acceptance on the execution ticket.
-
-Both gates are independent — swap can (and should) be added first, in a quiet window, before the full update is scheduled.
-
---
-
-## Current cp-1 workload (snapshot 2026-08-16)
-
-Re-derive live before any execution — this table is a design reference only.
-
-| Kind | Namespace/Name | Notes |
-|------|-----------------|-------|
-| StatefulSet | `harbor/harbor-database-0` | Harbor Postgres, RWO 10 GiB fsn1 |
-| StatefulSet | `harbor/harbor-redis-0` | Harbor cache, RWO 10 GiB fsn1 |
-| StatefulSet | `nextcloud/nextcloud-redis-replicas-0` | Nextcloud Redis replica, RWO 10 GiB fsn1 |
-| StatefulSet | `stalwart/stalwart-0` | Mail server, RWO 20 GiB fsn1 — **critical, move last** |
-| StatefulSet | `stalwart/stalwart-postgres-0` | Mail metadata DB, RWO 10 GiB fsn1 |
-| Deployment | `harbor/harbor-core` | Registry frontend, single replica |
-| Deployment | `harbor/harbor-jobservice` | Registry job worker, single replica |
-| Deployment | `monitoring/alertmanager` | Alertmanager, single replica |
-| Deployment | `monitoring/loki` | Loki (single-binary), single replica |
-| Deployment | `monitoring/prometheus` | Prometheus, single replica |
-| Deployment | `observability/blackbox-exporter-*` | Blackbox exporter |
-| Deployment | `opencloud/tika` | Apache Tika, single replica |
-| Deployment | `passbolt/passbolt` | Passbolt web, single replica |
-| DaemonSet | `kube-system/hcloud-csi-node-*` | Ignored by drain |
-| DaemonSet | `kube-system/svclb-*` | Ignored by drain |
-| DaemonSet | `observability/*-node-exporter-*` | Ignored by drain |
-| DaemonSet | `observability/loki-stack-promtail-*` | Ignored by drain |
-
-**Absorption capacity (fsn1 workers only — nbg1 worker-4 cannot receive fsn1 RWO volumes):**
-
- `k3s-worker-5`: ~3.0 GiB free, 6 pods scheduled — primary target for the two heaviest stateful pods.
- `k3s-worker-2`: ~2.0 GiB free, 14 pods.
- `k3s-worker-3`: ~2.3 GiB free, 15 pods, 2 sts.
- `k3s-worker-1`: ~1.9 GiB free, 23 pods, 6 sts — **avoid piling more onto this one**.
-
---
-
-## Phase A — Add swap (one-off, idempotent)
-
-**Goal:** eliminate the "3.7 GiB, no swap" underlying constraint before we ever try to drain cp-1.
-
-**Preconditions:**
-
- kubelet in this k3s already runs with `failSwapOn=false` (confirmed via `/api/v1/nodes/k3s-cp-1/proxy/configz`) — enabling swap does NOT break the kubelet.
- cp-1 `/` has ≥ 10 GiB free (currently 21 GiB free of 75 GiB).
- Board approval on the swap-add ticket.
-
-**Sizing:** default **4 GiB** swap. Rationale — cp-1 baseline (k3s + hosted apps) already sits at ~3.1 GiB used; 4 GiB swap gives us headroom for the drain-eviction transient without inflating disk usage past ~10 % of `/`. Minimum acceptable per guardrail: 2 GiB.
-
-**Location:** `/swapfile` (root filesystem). Not a separate partition — reversible, no LVM changes, no ext4/xfs migration.
-
-**Steps (encoded in `update-cp-1.sh --add-swap`):**
-
-```bash
-# On cp-1 as root:
-SWAPFILE=/swapfile
-SIZE_MB=4096
-
-# Idempotency: skip if a swapfile of the target size already exists and is on.
-if swapon --show=NAME | grep -qx "$SWAPFILE"; then
-  echo "swap already on at $SWAPFILE"
-  exit 0
-fi
-
-# Create the file with fallocate; fall back to dd for filesystems without fallocate support.
-fallocate -l "${SIZE_MB}M" "$SWAPFILE" || dd if=/dev/zero of="$SWAPFILE" bs=1M count="$SIZE_MB" status=progress
-chmod 600 "$SWAPFILE"
-mkswap "$SWAPFILE"
-swapon "$SWAPFILE"
-
-# Persist across reboot. Guard against duplicate fstab entries.
-grep -q "^$SWAPFILE " /etc/fstab || echo "$SWAPFILE none swap sw 0 0" >> /etc/fstab
-
-# Moderate swappiness — we want swap as a safety net, not aggressive paging.
-sysctl -w vm.swappiness=10
-grep -q '^vm.swappiness' /etc/sysctl.d/99-k3s-swap.conf 2>/dev/null || {
-  echo 'vm.swappiness=10' > /etc/sysctl.d/99-k3s-swap.conf
-}
-
-# Verify.
-free -h
-swapon --show
-```
-
-**Rollback for Phase A:** `swapoff /swapfile && rm /swapfile` and remove the fstab line. This is safe at any time — swap is a soft resource.
-
-**Verification after Phase A:**
-
- `free -h` shows `Swap: 4.0Gi` used ≈ 0.
- `swapon --show` shows `/swapfile 4G`.
- `sysctl vm.swappiness` returns `10`.
- kubelet still Ready (`kubectl get node k3s-cp-1`).
- No new `MemoryPressure` condition.
-
---
-
-## Phase B — Preflight for the full OS update
-
-Everything from here on runs from the CTO's operator machine (not from cp-1 itself, because we lose kubectl during the reboot). SSH to cp-1 is fine — kubectl calls issued from cp-1 during the pre-drain phase are fine and get logged into `/tmp/os-update-cp-1-<ts>.log`.
-
-**Log directory contract** (same as `update-node.sh`): every command's stdout+stderr goes to `/tmp/os-update-cp-1-<UTC-timestamp>.log` on cp-1. Attach that log to the Paperclip execution ticket at the end.
-
-Run `update-cp-1.sh --preflight`:
-
-1. Cluster is currently healthy: `cluster-health.sh` returns 0.
-2. All 5 fsn1 workers are `Ready` (worker-1, worker-2, worker-3, worker-5, cp-1). worker-4 is nbg1 and irrelevant here.
-3. Each fsn1 worker has ≥ 500 MiB `MemAvailable`.
-4. `time kubectl get nodes` returns in ≤ 2 s (kine is not already stressed).
-5. cp-1 has swap on — abort if `free -h` shows `Swap: 0B`.
-6. **k3s datastore snapshot.** cp-1 runs k3s in embedded-SQLite mode (`--datastore-endpoint` is unset). `k3s etcd-snapshot save --name pre-cp1-os-update-<UTC-date>` produces a copy of the SQLite file under `/var/lib/rancher/k3s/server/db/snapshots/`. This is our restore point. Snapshots older than 30 days are pruned in Phase F.
-
-If any preflight check fails: STOP. Do not proceed. Do not add pods to cp-1 to "rebalance later" — that's a separate task.
-
---
-
-## Phase C — Move stateful pods off cp-1 (batched)
-
-**Rule** ([[k3s-drain-kine-thundering-herd]] guardrail #1): no drain that reschedules > 3 StatefulSets at once. So we DO NOT `kubectl drain k3s-cp-1` while stateful pods still live on it. We move them one at a time first.
-
-**Cordon cp-1 immediately.** Cordon only prevents *new* scheduling — existing pods stay put. Cordoning first ensures that when we delete a stateful pod, the StatefulSet controller cannot re-create it back on cp-1.
-
-```bash
-kubectl cordon k3s-cp-1
-```
-
-**Order of eviction (idle → active, tiny → heavy):**
-
-| # | Pod | Why in this position |
-|---|-----|----------------------|
-| 1 | `harbor/harbor-redis-0` | Idle cache, cold restart is instant, low write pressure |
-| 2 | `nextcloud/nextcloud-redis-replicas-0` | Replica-1 of a Redis replicaset — non-primary, safe to bounce |
-| 3 | `harbor/harbor-database-0` | Registry Postgres, mostly idle (registry pulls, not writes) |
-| 4 | `stalwart/stalwart-postgres-0` | Mail metadata DB — active but recoverable; move before the mail server itself |
-| 5 | `stalwart/stalwart-0` | Mail server, most important. Save for last so mail keeps flowing until the very end |
-
-For each pod:
-
-```bash
-# 1. Delete the pod — StatefulSet controller will re-create it on a schedulable fsn1 worker.
-kubectl -n "$NS" delete pod "$POD" --wait=false
-
-# 2. Wait for the *new* pod (same name — StatefulSets keep identities) to be scheduled
-#    somewhere OTHER than cp-1 and reach Ready=True.
-deadline=$(( $(date +%s) + 300 ))
-while [ $(date +%s) -lt $deadline ]; do
-  new_node=$(kubectl -n "$NS" get pod "$POD" -o jsonpath='{.spec.nodeName}' 2>/dev/null || true)
-  ready=$(kubectl -n "$NS" get pod "$POD" -o jsonpath='{.status.conditions[?(@.type=="Ready")].status}' 2>/dev/null || true)
-  if [ -n "$new_node" ] && [ "$new_node" != "k3s-cp-1" ] && [ "$ready" = "True" ]; then
-    echo "  $POD -> $new_node OK"
-    break
-  fi
-  sleep 5
-done
-[ "$ready" = "True" ] || die "pod $NS/$POD did not reach Ready on a non-cp-1 node in 300s — HALT"
-
-# 3. Kine health probe — abort the batch if the api server is getting slow.
-t=$( { time kubectl get nodes >/dev/null; } 2>&1 | awk '/real/{print $2}' )
-# t is like "0m1.234s" — if the m field is >0 or the s field is >5, halt.
-# See update-cp-1.sh for the exact parse; > 5 s -> halt the whole cycle.
-
-# 4. Free-memory probe on cp-1.
-avail=$(ssh root@cp-1 "free -m | awk '/Mem:/{print \$7}'")
-[ "$avail" -lt 200 ] && die "cp-1 MemAvailable dropped below 200 MiB — HALT"
-
-# 5. Settle pause before the next eviction — kine needs to catch up on the write
-#    burst from the just-attached PV and the just-scheduled pod.
-sleep 60
-```
-
-**Halt conditions during Phase C** (any one → STOP, do NOT proceed to Phase D):
-
- `kubectl get nodes` takes > 5 s.
- cp-1 `MemAvailable` drops below 200 MiB.
- Any target worker enters `MemoryPressure=True` or `DiskPressure=True`.
- Any stateful pod does not reach Ready on a new node within 5 minutes (may indicate PV-attach or PDB issue).
-
-If we halt: leave cp-1 **cordoned** but do not reboot. The pods that have already moved stay where they are; the pods that haven't will still be on cp-1. Escalate on the execution ticket with `blocked` and name the halt condition.
-
---
-
-## Phase D — Drain remaining pods + apt
-
-Once all 5 stateful pods are off cp-1 and cluster health is green:
-
-```bash
-# Drain everything else — only Deployment pods left (single-replica each,
-# no PV attach, so reschedule is fast).
-kubectl drain k3s-cp-1 \
-  --ignore-daemonsets \
-  --delete-emptydir-data \
-  --timeout="${DRAIN_TIMEOUT_SECONDS:-600}s"
-```
-
-If drain reports a PDB block: do NOT `--force`. Uncordon cp-1, mark the run as `blocked` on the PDB, and escalate. This is a design bug in the workload's PDB — fix it separately.
-
-**apt on cp-1** (mirrors `update-node.sh` step 3; `update-cp-1.sh --apt` runs this via `ssh root@cp-1 bash -s`):
-
-```bash
-export DEBIAN_FRONTEND=noninteractive
-APT_OPTS='-y -o Dpkg::Options::=--force-confdef -o Dpkg::Options::=--force-confold'
-uname -r > /root/pre-apt-kernel   # for rollback reference
-dpkg-query -W -f='${Package}\t${Version}\n' > /root/pre-apt-packages.tsv
-
-if dpkg --audit | grep -qE .; then dpkg --configure -a || true; fi
-apt-get update
-apt-get $APT_OPTS upgrade || { apt-get $APT_OPTS -f install; apt-get $APT_OPTS upgrade; }
-apt-get $APT_OPTS dist-upgrade
-apt-get $APT_OPTS autoremove --purge
-apt-get clean
-[ -f /var/run/reboot-required ] && echo REBOOT_REQUIRED=yes || echo REBOOT_REQUIRED=no
-```
-
-`pre-apt-kernel` and `pre-apt-packages.tsv` are the local rollback references — see Rollback below.
-
---
-
-## Phase E — Reboot handling (api-server unavailability)
-
-**Duration expectation:** 90–180 s of api-server unavailability. The operator machine will get `Unable to connect to the server` from kubectl during this window — that is expected, not an alarm.
-
-**Escalation trigger:** api-server not back on `/livez` after **10 minutes** → escalate. First check Hetzner console via `hcloud server describe k3s-cp-1` for boot state; if kernel-panic / initramfs, use grub previous-kernel path (see Rollback). Do NOT rebuild the node.
-
-**Steps (executed by `update-cp-1.sh --reboot`):**
-
-```bash
-# 1. Tell cp-1 to reboot. This SSH will hang up mid-command — that's fine.
-ssh $SSH_OPTS root@cp-1 'systemctl reboot' || true
-
-# 2. Deliberate 15 s pause — SSH needs to actually drop, don't race the poll.
-sleep 15
-
-# 3. Poll the api-server livez from the OPERATOR machine (not from cp-1).
-#    Using --insecure (`-k`) because the server cert is self-signed by k3s.
-deadline=$(( $(date +%s) + ${REBOOT_MAX_WAIT_SECONDS:-600} ))
-while [ $(date +%s) -lt $deadline ]; do
-  code=$(curl -sk -o /dev/null -w '%{http_code}' https://178.105.17.239:6443/livez 2>/dev/null || echo 000)
-  if [ "$code" = "200" ]; then
-    echo "  api-server /livez=200"
-    break
-  fi
-  sleep 5
-done
-[ "$code" = "200" ] || die "api-server did not return within ${REBOOT_MAX_WAIT_SECONDS}s — escalate; check hcloud console"
-
-# 4. Wait for kubelet Ready on cp-1 from the api-server view.
-deadline=$(( $(date +%s) + 300 ))
-while [ $(date +%s) -lt $deadline ]; do
-  ready=$(kubectl get node k3s-cp-1 -o jsonpath='{.status.conditions[?(@.type=="Ready")].status}' 2>/dev/null || echo Unknown)
-  [ "$ready" = "True" ] && break
-  sleep 5
-done
-[ "$ready" = "True" ] || die "kubelet on cp-1 never returned Ready — escalate (do NOT change k3s config)"
-```
-
-**What to do if the api-server takes 3–10 minutes:** it may be normal on this box (large SQLite → replay). Wait it out. Do NOT restart k3s to "help" — kine SQLite replay is stateful and interrupting it can corrupt the DB. See [[k3s-drain-kine-thundering-herd]] recovery: doing nothing is a valid path.
-
-**What to do if it takes > 10 minutes:** escalate; run the Hetzner-console diagnosis; if the console shows a bootable Ubuntu but the k3s service is failing, that's the boundary — this procedure stops here. Follow `K3S_OPERATIONS.md` for the k3s recovery path.
-
---
-
-## Phase F — Uncordon + verify + finalize
-
-```bash
-# Uncordon cp-1. StatefulSet pods will NOT be moved back — that's correct
-# behaviour, they were moved for a reason. Rebalancing is a separate task.
-kubectl uncordon k3s-cp-1
-
-# Settle wait — kine needs to process the flood of "node schedulable again" events.
-sleep "${POST_UNCORDON_WAIT_SECONDS:-180}"
-
-# Full cluster health.
-RETRY_ON_TRANSIENT=1 infrastructure/scripts/os-update/cluster-health.sh
-
-# Print the apt history for audit.
-ssh root@cp-1 'zgrep -h "Commandline\|Install\|Upgrade\|Remove" /var/log/apt/history.log* 2>/dev/null | tail -60'
-
-# Prune snapshots older than 30 days.
-ssh root@cp-1 'find /var/lib/rancher/k3s/server/db/snapshots/ -type f -mtime +30 -name "pre-*" -print'
-# (list only — actual deletion is a manual review after the run)
-```
-
-Attach the `/tmp/os-update-cp-1-<ts>.log` and the ordered ledger of moved pods to the execution ticket. Mark the ticket `done` on green health, or `blocked` naming the specific residual issue on red.
-
---
-
-## Rollback / recovery
-
-### If apt broke a package
-
- On cp-1, `dpkg --audit` to find half-configured packages.
- `dpkg --configure -a`, then `apt-get -f install`.
- If a specific package broke and you know the previous version from `/root/pre-apt-packages.tsv`, `apt-get install <pkg>=<old-version>`.
-
-### If the new kernel does not boot
-
- Hetzner cloud console: send `hcloud server request-console k3s-cp-1` → get VNC URL, watch boot.
- If grub is up, select the previous-kernel entry. Ubuntu keeps ≥ 1 old kernel installed by default (we verified `6.8.0-137` current; the previous `6.8.0-124` was in use during the DEV-478 cycle).
- Once booted on the old kernel, `apt-get remove` the broken kernel and pin the working one:
-  ```bash
-  apt-mark hold linux-image-<broken-version> linux-headers-<broken-version>
-  ```
- Escalate on the ticket regardless — a kernel rollback is a follow-up investigation, not a "done" outcome.
-
-### If the node does not return at all
-
- Do NOT `hcloud server delete`. Do NOT re-provision.
- Escalate to the board with the Hetzner console output and the `/tmp/os-update-cp-1-*.log`.
- The `--cluster-reset --cluster-reset-restore-path=<snapshot>` recovery path exists (see `K3S_OPERATIONS.md`) but requires board approval per stateful-service safety rules. The pre-flight snapshot from Phase B is the restore point.
-
-### If Phase C halted mid-eviction
-
- cp-1 is cordoned, some stateful pods have moved, some haven't. Cluster is functional.
- Uncordon cp-1 (`kubectl uncordon k3s-cp-1`) — StatefulSets that stayed on cp-1 keep running, moved ones stay where they went.
- Do NOT proceed to Phase D. Open a follow-up ticket with the halt condition. Retry in the next maintenance window after fixing the halt condition.
-
---
-
-## Automation entry points
-
- `infrastructure/scripts/os-update/update-cp-1.sh` — this whole flow, with subcommands:
-  - `--add-swap` — Phase A only, idempotent, safe standalone.
-  - `--dry-run` — walk Phases B/C/D/E/F printing exactly what would be done without touching anything. Safe to run any time; used for design review.
-  - `--preflight` — Phase B only.
-  - `--drain-stateful` — Phase C only (cordon + batched stateful moves).
-  - `--apt` — Phase D apt commands only (requires cp-1 already fully drained).
-  - `--reboot` — Phase E only (requires apt already done).
-  - `--finalize` — Phase F only (uncordon + verify).
-  - `--run` — do all phases in order, with a confirmation prompt between each unless `ASSUME_YES=1`.
-
-The script follows the same log-dir contract as `update-node.sh` (`/tmp/os-update-cp-1-<UTC-timestamp>.log`).
-
---
-
-## Change history
-
-| Date | Change | By |
-|------|--------|-----|
-| 2026-08-16 | Initial cp-1 update design (DEV-496) | CTO agent |
--- a/infrastructure/OS_UPDATE_PROCEDURE.md
+++ b/infrastructure/OS_UPDATE_PROCEDURE.md
@ -40,7 +40,7 @@ ssh root@178.105.17.239 'kubectl get nodes -o wide'
 1. runner + workers that host no PVs (safest — lowest disruption)
 2. remaining workers
 3. **Stalwart-hosting fsn1 workers last among workers** — Stalwart has hard fsn1 affinity, so draining a fsn1 worker while another fsn1 worker is also unavailable can leave Stalwart Pending. Never have two fsn1 workers cordoned/down at the same time.
-4. **k3s-cp-1 excluded** — single control plane; has its own dedicated procedure and script. See `CP1_UPDATE_PROCEDURE.md` and `scripts/os-update/update-cp-1.sh`.
+4. **k3s-cp-1 last** — single control plane; the API server goes away during its reboot.

 **Concurrency:** exactly one node at a time. Never in parallel.

@ -55,7 +55,7 @@ All four rules below MUST be observed on every DEV-478 fire. The reference imple
 1. **Pre-plan drain order for StatefulSets.** Before draining any worker, `kubectl get pods -n <ns> -o wide` against every namespace with StatefulSets and count how many will be evicted from the target node. If a single drain would evict **more than 3 StatefulSets at once**, redistribute first: cordon+delete individual StatefulSet pods one namespace at a time and wait for each reschedule to settle before draining the whole node.
 2. **cp-1 must have swap before finishing the cycle.** cp-1 has 0 swap. Add at least 2 GiB of swap on cp-1 before the cp-1 update step (and ideally before draining the last stateful-heavy worker). This is a one-off setup task; once done it is a durable capability.
 3. **Halt on kine slowness.** During any drain, keep a `time kubectl get nodes` running from cp-1. If it exceeds **5 s** in real time, halt the cycle immediately (uncordon the current node, do not proceed), verify cluster health, and escalate. The 5 s threshold is the leading indicator that kine has fallen behind and the taint-eviction cascade is about to start.
-4. **cp-1 update is a separate design task.** Draining cp-1's own pods (Stalwart, coredns, harbor-database if there, etc.) plus rebooting the single apiserver is the highest-risk step of the whole cycle. It MUST be planned and approved as a distinct issue before it runs; it is NOT covered by the standard `os-update.sh` cycle. See `CP1_UPDATE_PROCEDURE.md` and `scripts/os-update/update-cp-1.sh` (DEV-496).
+4. **cp-1 update is a separate design task.** Draining cp-1's own pods (Stalwart, coredns, harbor-database if there, etc.) plus rebooting the single apiserver is the highest-risk step of the whole cycle. It MUST be planned and approved as a distinct issue before it runs; it is NOT covered by the standard `os-update.sh` cycle in its current form.

 ---

@ -237,13 +237,10 @@ Only proceed to the next node when ALL of the above are green. If not:

 ### 8. Control plane special handling

-`k3s-cp-1` is the single control plane node and is **NOT** updated by the weekly `os-update.sh` cycle — it has its own dedicated procedure and script. See `CP1_UPDATE_PROCEDURE.md` and `scripts/os-update/update-cp-1.sh`. Reasons:
-
- cp-1 hosts many stateful pods (currently 5 StatefulSets + 8 single-replica Deployments) — a one-shot `kubectl drain` would trigger the kine/SQLite cascade documented in the "Kine thundering-herd guardrails" section above (DEV-495).
- cp-1 has 3.7 GiB RAM and (until Phase A of the cp-1 procedure is done) zero swap. The cp-1 procedure adds a durable 4 GiB swapfile before draining.
- Rebooting cp-1 removes the entire kube-apiserver — the cp-1 procedure polls `/livez` from an external operator machine, not from cp-1 itself.
-
-`os-update.sh` will `SKIP` cp-1 and print a pointer to `CP1_UPDATE_PROCEDURE.md`.
+`k3s-cp-1` is the single control plane node. During its reboot:
+- The kube-apiserver is unavailable — kubectl commands from the operator machine will error out.
+- The `kubectl` waits in step 5/7 must run from a machine that is NOT the control plane, or must be scheduled after the control plane's SSH is back and `curl -k https://localhost:6443/healthz` returns `ok`.
+- Skip the drain for DaemonSet pods on the control plane (`--ignore-daemonsets` covers that), but hosted apps that scheduled onto CP (rare — verify with `kubectl get pods -A --field-selector spec.nodeName=k3s-cp-1`) will be evicted.

 ---

@ -304,9 +301,8 @@ If a node was skipped or errored → mark `blocked` with the unblock action, or

 ## Automation entry points

- `infrastructure/scripts/os-update/os-update.sh` — full cycle runner (preflight → per-node loop → finalization). Idempotent, resumable via `--start-from <node>`. Use `--dry-run` to print the plan without touching anything. Explicitly skips `k3s-cp-1`.
- `infrastructure/scripts/os-update/update-node.sh <node>` — single-node update (all 7 per-node steps). Callable standalone for retry. Not for `k3s-cp-1`.
- `infrastructure/scripts/os-update/update-cp-1.sh` — dedicated cp-1 update flow (add swap, batched stateful eviction, apt, reboot with external liveness monitor). See `CP1_UPDATE_PROCEDURE.md`.
+- `infrastructure/scripts/os-update/os-update.sh` — full cycle runner (preflight → per-node loop → finalization). Idempotent, resumable via `--start-from <node>`. Use `--dry-run` to print the plan without touching anything.
+- `infrastructure/scripts/os-update/update-node.sh <node>` — single-node update (all 7 per-node steps). Callable standalone for retry.
 - `infrastructure/scripts/os-update/cluster-health.sh` — the preflight/post-node health check as a standalone command; exits non-zero on any failure.

 Read the script sources for the exact behavior before running them. They mirror this procedure step for step.
--- a/infrastructure/scripts/os-update/os-update.sh
+++ b/infrastructure/scripts/os-update/os-update.sh
@ -68,11 +68,9 @@ fi

 # --- 3. node ordering ---------------------------------------------------------
 # Ordering rule:
-#   - workers only
+#   - workers before control plane
 #   - within workers: nodes NOT hosting Stalwart first, Stalwart-hosting fsn1 nodes last
-#   - k3s-cp-1 is EXCLUDED and never updated by this script — see CP1_UPDATE_PROCEDURE.md
-#     and scripts/os-update/update-cp-1.sh. The rationale is the kine thundering-herd
-#     guardrails documented in OS_UPDATE_PROCEDURE.md (added after DEV-495).
+#   - k3s-cp-1 always last
 STALWART_NODE=$(kubectl -n stalwart get pod -l app=stalwart -o jsonpath='{.items[*].spec.nodeName}' 2>/dev/null | tr ' ' '\n' | sort -u || true)
 # If the pod's not currently up (e.g. Pending) we still want to protect fsn1 workers.
 CP_NAME="k3s-cp-1"
@ -96,11 +94,7 @@ for n in $ALL_NODES; do
  fi
 done

-ORDER=("${workers[@]}" "${stalwart_workers[@]}")
-# NOTE: cp-1 intentionally excluded. To update cp-1, run `scripts/os-update/update-cp-1.sh`.
-if printf '%s\n' "$ALL_NODES" | grep -qx "$CP_NAME"; then
-  log "[plan] EXCLUDING $CP_NAME — use scripts/os-update/update-cp-1.sh (see CP1_UPDATE_PROCEDURE.md)"
-fi
+ORDER=("${workers[@]}" "${stalwart_workers[@]}" "$CP_NAME")

 if [ -n "$ONLY" ]; then
  ORDER=("$ONLY")
--- a/infrastructure/scripts/os-update/update-cp-1.sh
+++ b/infrastructure/scripts/os-update/update-cp-1.sh
@ -1,577 +0,0 @@
-#!/bin/bash
-# update-cp-1.sh — controlled OS update for the k3s control-plane node.
-#
-# See ../CP1_UPDATE_PROCEDURE.md for the full design rationale.
-#
-# Usage:
-#   update-cp-1.sh --dry-run           # print what would be done, touch nothing
-#   update-cp-1.sh --add-swap          # Phase A only (idempotent, safe standalone)
-#   update-cp-1.sh --preflight         # Phase B only
-#   update-cp-1.sh --drain-stateful    # Phase C only  (cordon + batched sts moves)
-#   update-cp-1.sh --apt               # Phase D only  (requires cp-1 fully drained)
-#   update-cp-1.sh --reboot            # Phase E only  (requires --apt reported REBOOT_REQUIRED=yes)
-#   update-cp-1.sh --finalize          # Phase F only  (uncordon + verify)
-#   update-cp-1.sh --run               # all phases with a confirmation between each (or ASSUME_YES=1)
-#
-# Environment overrides:
-#   CP1_HOST                     default 178.105.17.239
-#   SWAP_SIZE_MB                 default 4096       (>=2048 required)
-#   SWAP_PATH                    default /swapfile
-#   DRAIN_TIMEOUT_SECONDS        default 600
-#   REBOOT_MAX_WAIT_SECONDS      default 600
-#   POST_UNCORDON_WAIT_SECONDS   default 180
-#   STATEFUL_SETTLE_SECONDS      default 60         (pause between batched sts moves)
-#   MIN_WORKER_MEM_MIB           default 500        (per-worker MemAvailable floor at preflight)
-#   MIN_CP1_MEM_MIB              default 200        (cp-1 MemAvailable floor mid-drain)
-#   MAX_KUBECTL_SECONDS          default 5          (kine-health guardrail)
-#   SSH_OPTS                     default "-o ConnectTimeout=10 -o StrictHostKeyChecking=accept-new"
-#   ASSUME_YES=1                 skip interactive confirmations in --run
-#   DRY_RUN=1                    do not execute state-mutating commands; log-only
-#
-# Log directory contract (matches update-node.sh):
-#   Every command's stdout+stderr is tee'd to /tmp/os-update-cp-1-<UTC-ts>.log on
-#   the operator machine AND to /tmp/os-update-cp-1-<UTC-ts>.log on cp-1 (via the
-#   ssh command wrappers). Attach both to the execution ticket at the end.
-#
-# NEVER touches k3s config, k3s services, containerd, or any manifest. Only
-# fixes it will attempt: apt/dpkg recovery on cp-1 (see Phase D). Any other
-# problem → escalate and STOP.
-
-set -euo pipefail
-
-# --------------------------------------------------------------------------- #
-# Config
-# --------------------------------------------------------------------------- #
-CP1_HOST="${CP1_HOST:-178.105.17.239}"
-SWAP_SIZE_MB="${SWAP_SIZE_MB:-4096}"
-SWAP_PATH="${SWAP_PATH:-/swapfile}"
-DRAIN_TIMEOUT_SECONDS="${DRAIN_TIMEOUT_SECONDS:-600}"
-REBOOT_MAX_WAIT_SECONDS="${REBOOT_MAX_WAIT_SECONDS:-600}"
-POST_UNCORDON_WAIT_SECONDS="${POST_UNCORDON_WAIT_SECONDS:-180}"
-STATEFUL_SETTLE_SECONDS="${STATEFUL_SETTLE_SECONDS:-60}"
-MIN_WORKER_MEM_MIB="${MIN_WORKER_MEM_MIB:-500}"
-MIN_CP1_MEM_MIB="${MIN_CP1_MEM_MIB:-200}"
-MAX_KUBECTL_SECONDS="${MAX_KUBECTL_SECONDS:-5}"
-SSH_OPTS="${SSH_OPTS:--o ConnectTimeout=10 -o StrictHostKeyChecking=accept-new}"
-DRY_RUN="${DRY_RUN:-0}"
-ASSUME_YES="${ASSUME_YES:-0}"
-
-NODE="k3s-cp-1"
-TS="$(date -u +%Y%m%dT%H%M%SZ)"
-LOG_LOCAL="/tmp/os-update-cp-1-${TS}.log"
-LOG_REMOTE="/tmp/os-update-cp-1-${TS}.log"
-
-SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
-HEALTH_SCRIPT="$SCRIPT_DIR/cluster-health.sh"
-
-# --------------------------------------------------------------------------- #
-# Stateful eviction ledger — order matters (idle -> active, small -> heavy).
-# --------------------------------------------------------------------------- #
-# The list is derived live from the cluster in preflight and stored to
-# /tmp/cp1-stateful-plan-<ts>.txt. This ORDER is the authoritative fallback.
-STATEFUL_ORDER=(
-  "harbor:harbor-redis-0"
-  "nextcloud:nextcloud-redis-replicas-0"
-  "harbor:harbor-database-0"
-  "stalwart:stalwart-postgres-0"
-  "stalwart:stalwart-0"
-)
-
-# --------------------------------------------------------------------------- #
-# Logging + safe-run helpers
-# --------------------------------------------------------------------------- #
-log()  { echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] $*" | tee -a "$LOG_LOCAL"; }
-die()  { log "FATAL: $*"; exit 1; }
-warn() { log "WARN:  $*"; }
-
-# run/ssh_run/kubectl_run: honour DRY_RUN — print, do not execute state changes.
-run() {
-  if [ "$DRY_RUN" = "1" ]; then
-    log "DRY-RUN would exec: $*"
-    return 0
-  fi
-  log "exec: $*"
-  "$@" 2>&1 | tee -a "$LOG_LOCAL"
-}
-
-ssh_run() {
-  local target="root@${CP1_HOST}"
-  if [ "$DRY_RUN" = "1" ]; then
-    log "DRY-RUN would ssh $target: $*"
-    return 0
-  fi
-  log "ssh $target: $*"
-  ssh $SSH_OPTS "$target" "$@" 2>&1 | tee -a "$LOG_LOCAL"
-}
-
-# ssh_run_stdin: pipe a heredoc through bash -s on cp-1; used for multi-line remote
-# blocks (swap add, apt).
-ssh_run_stdin() {
-  local target="root@${CP1_HOST}"
-  if [ "$DRY_RUN" = "1" ]; then
-    log "DRY-RUN would ssh $target with stdin script:"
-    sed 's/^/    | /' | tee -a "$LOG_LOCAL"
-    return 0
-  fi
-  log "ssh $target (heredoc)"
-  ssh $SSH_OPTS "$target" "bash -s" 2>&1 | tee -a "$LOG_LOCAL"
-}
-
-confirm() {
-  local prompt="$1"
-  if [ "$ASSUME_YES" = "1" ]; then
-    log "confirm SKIPPED (ASSUME_YES=1): $prompt"
-    return 0
-  fi
-  echo -n "  >>> $prompt  Continue? [y/N] "
-  read -r a
-  case "$a" in y|Y|yes|YES) return 0 ;; *) die "aborted by operator" ;; esac
-}
-
-# --------------------------------------------------------------------------- #
-# Phase A — Add swap on cp-1 (idempotent)
-# --------------------------------------------------------------------------- #
-phase_add_swap() {
-  log "=== Phase A: add swap on $NODE ($SWAP_SIZE_MB MiB at $SWAP_PATH) ==="
-  [ "$SWAP_SIZE_MB" -ge 2048 ] || die "SWAP_SIZE_MB=$SWAP_SIZE_MB below 2048 MiB guardrail"
-
-  cat <<REMOTE | ssh_run_stdin
-set -euo pipefail
-SWAP_PATH="$SWAP_PATH"
-SIZE_MB="$SWAP_SIZE_MB"
-
-# Skip if a swapfile at this path is already active.
-if swapon --show=NAME 2>/dev/null | grep -qx "\$SWAP_PATH"; then
-  echo "swap already on at \$SWAP_PATH — skipping"
-  free -h
-  exit 0
-fi
-
-# Root filesystem free space check — abort if less than 2*swap free.
-avail_mb=\$(df -m --output=avail / | tail -1 | tr -d ' ')
-need_mb=\$(( SIZE_MB * 2 ))
-if [ "\$avail_mb" -lt "\$need_mb" ]; then
-  echo "ERROR: only \${avail_mb} MiB free on /, need \${need_mb} MiB (2x swap for safety)"
-  exit 1
-fi
-
-# Create swapfile. fallocate is fast; dd is the fallback.
-if ! fallocate -l "\${SIZE_MB}M" "\$SWAP_PATH" 2>/dev/null; then
-  dd if=/dev/zero of="\$SWAP_PATH" bs=1M count="\$SIZE_MB" status=progress
-fi
-chmod 600 "\$SWAP_PATH"
-mkswap "\$SWAP_PATH"
-swapon "\$SWAP_PATH"
-
-# Persist via fstab (dedup).
-if ! grep -q "^\$SWAP_PATH " /etc/fstab; then
-  echo "\$SWAP_PATH none swap sw 0 0" >> /etc/fstab
-fi
-
-# Moderate swappiness — swap as safety net, not aggressive paging.
-sysctl -w vm.swappiness=10
-if [ ! -f /etc/sysctl.d/99-k3s-swap.conf ] || ! grep -q '^vm.swappiness' /etc/sysctl.d/99-k3s-swap.conf; then
-  echo 'vm.swappiness=10' > /etc/sysctl.d/99-k3s-swap.conf
-fi
-
-echo "--- swap after ---"
-free -h
-swapon --show
-sysctl vm.swappiness
-REMOTE
-
-  # Verify from operator view.
-  if [ "$DRY_RUN" != "1" ]; then
-    log "verifying kubelet still Ready after swap add"
-    local ready
-    ready=$(kubectl get node "$NODE" -o jsonpath='{.status.conditions[?(@.type=="Ready")].status}')
-    [ "$ready" = "True" ] || die "kubelet on $NODE not Ready after swap add — halt"
-    log "kubelet Ready=True — Phase A complete"
-  fi
-}
-
-# --------------------------------------------------------------------------- #
-# Guardrail probes
-# --------------------------------------------------------------------------- #
-kubectl_latency_s() {
-  # returns integer seconds elapsed for `kubectl get nodes >/dev/null`.
-  local start end
-  start=$(date +%s)
-  kubectl get nodes >/dev/null 2>&1 || echo "kubectl-error" >&2
-  end=$(date +%s)
-  echo $(( end - start ))
-}
-
-cp1_mem_available_mib() {
-  # returns integer MiB `MemAvailable` on cp-1.
-  ssh $SSH_OPTS "root@$CP1_HOST" "awk '/^MemAvailable:/{printf \"%d\n\", \$2/1024}' /proc/meminfo" 2>/dev/null || echo 0
-}
-
-guard_kine_healthy() {
-  local s
-  s=$(kubectl_latency_s)
-  if [ "$s" -gt "$MAX_KUBECTL_SECONDS" ]; then
-    die "kubectl get nodes took ${s}s (>${MAX_KUBECTL_SECONDS}s) — kine cascade risk, HALT"
-  fi
-  log "  kine ok: kubectl get nodes took ${s}s"
-}
-
-guard_cp1_memory() {
-  local m
-  m=$(cp1_mem_available_mib)
-  if [ "$m" -lt "$MIN_CP1_MEM_MIB" ]; then
-    die "cp-1 MemAvailable=${m} MiB below ${MIN_CP1_MEM_MIB} MiB floor — HALT"
-  fi
-  log "  cp-1 mem ok: MemAvailable=${m} MiB"
-}
-
-# --------------------------------------------------------------------------- #
-# Phase B — Preflight
-# --------------------------------------------------------------------------- #
-phase_preflight() {
-  log "=== Phase B: preflight ==="
-
-  log "-- cluster health"
-  if [ "$DRY_RUN" != "1" ]; then
-    if ! RETRY_ON_TRANSIENT=1 "$HEALTH_SCRIPT" 2>&1 | tee -a "$LOG_LOCAL"; then
-      die "cluster is not healthy — refuse to start cp-1 update"
-    fi
-  else
-    log "DRY-RUN would run: $HEALTH_SCRIPT"
-  fi
-
-  log "-- swap on cp-1"
-  if [ "$DRY_RUN" != "1" ]; then
-    local swap_total
-    swap_total=$(ssh $SSH_OPTS "root@$CP1_HOST" "awk '/^SwapTotal:/{print \$2}' /proc/meminfo")
-    [ "${swap_total:-0}" -ge $((2 * 1024 * 1024)) ] \
-      || die "cp-1 SwapTotal=${swap_total} KiB below 2 GiB — run --add-swap first"
-    log "  cp-1 SwapTotal=$(( swap_total / 1024 )) MiB"
-  fi
-
-  log "-- fsn1 workers Ready and have >=${MIN_WORKER_MEM_MIB} MiB MemAvailable"
-  # Worker private IPs (worker-4 nbg1 excluded — cannot host fsn1 RWO PVs).
-  local ips=("10.42.1.2" "10.42.1.3" "10.42.1.5" "10.42.1.7")
-  local names=("k3s-worker-1" "k3s-worker-2" "k3s-worker-3" "k3s-worker-5")
-  if [ "$DRY_RUN" != "1" ]; then
-    for i in "${!ips[@]}"; do
-      local nm="${names[$i]}"
-      local ip="${ips[$i]}"
-      local ready
-      ready=$(kubectl get node "$nm" -o jsonpath='{.status.conditions[?(@.type=="Ready")].status}' 2>/dev/null || echo Unknown)
-      [ "$ready" = "True" ] || die "worker $nm not Ready (Ready=$ready)"
-      local mem
-      mem=$(ssh $SSH_OPTS -J "root@$CP1_HOST" "root@$ip" \
-        "awk '/^MemAvailable:/{printf \"%d\n\", \$2/1024}' /proc/meminfo" 2>/dev/null || echo 0)
-      [ "$mem" -ge "$MIN_WORKER_MEM_MIB" ] \
-        || die "worker $nm MemAvailable=${mem} MiB below ${MIN_WORKER_MEM_MIB} MiB — HALT"
-      log "  $nm ok: MemAvailable=${mem} MiB"
-    done
-  fi
-
-  log "-- kine latency probe"
-  if [ "$DRY_RUN" != "1" ]; then guard_kine_healthy; fi
-
-  log "-- k3s SQLite datastore snapshot"
-  # k3s etcd-snapshot in embedded-SQLite mode copies the sqlite file to
-  # /var/lib/rancher/k3s/server/db/snapshots/.
-  ssh_run "k3s etcd-snapshot save --name pre-cp1-os-update-${TS}"
-  ssh_run "ls -la /var/lib/rancher/k3s/server/db/snapshots/ | tail -10"
-
-  log "-- persist eviction plan"
-  if [ "$DRY_RUN" != "1" ]; then
-    local plan="/tmp/cp1-stateful-plan-${TS}.txt"
-    ssh $SSH_OPTS "root@$CP1_HOST" "cat > $plan" <<EOF
-# cp-1 stateful eviction plan generated at $TS
-# Order: idle -> active, small -> heavy. Do NOT reorder without design review.
-$(for e in "${STATEFUL_ORDER[@]}"; do echo "$e"; done)
-EOF
-    log "  wrote $plan on cp-1"
-  else
-    log "DRY-RUN would write /tmp/cp1-stateful-plan-${TS}.txt with STATEFUL_ORDER"
-  fi
-
-  log "=== Phase B: preflight OK ==="
-}
-
-# --------------------------------------------------------------------------- #
-# Phase C — Cordon + move stateful pods off cp-1, one at a time
-# --------------------------------------------------------------------------- #
-phase_drain_stateful() {
-  log "=== Phase C: cordon + batched stateful move ==="
-
-  log "-- cordon $NODE (prevents rescheduled pods from landing back on cp-1)"
-  run kubectl cordon "$NODE"
-
-  local i=0
-  for entry in "${STATEFUL_ORDER[@]}"; do
-    i=$((i + 1))
-    local ns="${entry%%:*}"
-    local pod="${entry##*:}"
-
-    log "--- [${i}/${#STATEFUL_ORDER[@]}] moving $ns/$pod"
-
-    # Confirm the pod actually IS on cp-1 before touching it.
-    if [ "$DRY_RUN" != "1" ]; then
-      local on
-      on=$(kubectl -n "$ns" get pod "$pod" -o jsonpath='{.spec.nodeName}' 2>/dev/null || echo "")
-      if [ -z "$on" ]; then
-        log "  $ns/$pod not found — sts may have changed; skipping"
-        continue
-      fi
-      if [ "$on" != "$NODE" ]; then
-        log "  $ns/$pod already on $on (not cp-1) — skipping"
-        continue
-      fi
-    fi
-
-    # Delete the pod. StatefulSet controller will re-create it; scheduler will
-    # pick a fsn1 worker because cp-1 is cordoned and worker-4 is nbg1.
-    run kubectl -n "$ns" delete pod "$pod" --wait=false
-
-    if [ "$DRY_RUN" = "1" ]; then
-      log "  DRY-RUN skipping wait-for-ready"
-      continue
-    fi
-
-    log "  waiting for $ns/$pod to be Ready on a non-cp-1 node (max 300s)"
-    local deadline=$(( $(date +%s) + 300 ))
-    local new_node="" ready=""
-    while [ $(date +%s) -lt $deadline ]; do
-      new_node=$(kubectl -n "$ns" get pod "$pod" -o jsonpath='{.spec.nodeName}' 2>/dev/null || echo "")
-      ready=$(kubectl -n "$ns" get pod "$pod" -o jsonpath='{.status.conditions[?(@.type=="Ready")].status}' 2>/dev/null || echo "")
-      if [ -n "$new_node" ] && [ "$new_node" != "$NODE" ] && [ "$ready" = "True" ]; then
-        log "  $ns/$pod -> $new_node OK"
-        break
-      fi
-      sleep 5
-    done
-    [ "$ready" = "True" ] && [ "$new_node" != "$NODE" ] \
-      || die "$ns/$pod did not reach Ready on a non-cp-1 node in 300s — HALT (leave cp-1 cordoned)"
-
-    log "  guardrails after $ns/$pod"
-    guard_kine_healthy
-    guard_cp1_memory
-
-    if [ "$i" -lt "${#STATEFUL_ORDER[@]}" ]; then
-      log "  settle pause ${STATEFUL_SETTLE_SECONDS}s"
-      sleep "$STATEFUL_SETTLE_SECONDS"
-    fi
-  done
-
-  log "=== Phase C: all stateful pods evicted from cp-1 ==="
-}
-
-# --------------------------------------------------------------------------- #
-# Phase D — Drain remaining pods + apt on cp-1
-# --------------------------------------------------------------------------- #
-phase_apt() {
-  log "=== Phase D: drain (remaining deployments) + apt on $NODE ==="
-
-  # Guardrail: refuse to run if any StatefulSet pod is still on cp-1.
-  if [ "$DRY_RUN" != "1" ]; then
-    local sts_on_cp1
-    sts_on_cp1=$(kubectl get pods -A -o json --field-selector spec.nodeName=$NODE \
-      | jq -r '.items[] | select(.metadata.ownerReferences[0].kind=="StatefulSet") | "\(.metadata.namespace)/\(.metadata.name)"' \
-      | wc -l)
-    [ "$sts_on_cp1" -eq 0 ] \
-      || die "$sts_on_cp1 StatefulSet pod(s) still on cp-1 — Phase C incomplete; refuse Phase D"
-  fi
-
-  log "-- drain (timeout ${DRAIN_TIMEOUT_SECONDS}s)"
-  set +e
-  if [ "$DRY_RUN" = "1" ]; then
-    log "DRY-RUN would run: kubectl drain $NODE --ignore-daemonsets --delete-emptydir-data --timeout=${DRAIN_TIMEOUT_SECONDS}s"
-    local rc=0
-  else
-    kubectl drain "$NODE" \
-      --ignore-daemonsets \
-      --delete-emptydir-data \
-      --timeout="${DRAIN_TIMEOUT_SECONDS}s" 2>&1 | tee -a "$LOG_LOCAL"
-    local rc=${PIPESTATUS[0]}
-  fi
-  set -e
-
-  if [ "$rc" -ne 0 ]; then
-    log "drain FAILED (rc=$rc). Never force. Uncordoning."
-    run kubectl uncordon "$NODE"
-    die "drain failed on $NODE — investigate PDB / orphan pods; do NOT proceed"
-  fi
-
-  log "-- apt on cp-1"
-  cat <<'REMOTE' | ssh_run_stdin
-set -euo pipefail
-export DEBIAN_FRONTEND=noninteractive
-APT_OPTS='-y -o Dpkg::Options::=--force-confdef -o Dpkg::Options::=--force-confold'
-
-# Rollback references (Phase-A didn't need this, but Phase D does).
-uname -r > /root/pre-apt-kernel
-dpkg-query -W -f='${Package}\t${Version}\n' > /root/pre-apt-packages.tsv
-echo "pre-apt kernel: $(cat /root/pre-apt-kernel)"
-
-# Recover from any half-finished dpkg state before touching apt.
-if dpkg --audit | grep -qE .; then
-  echo "dpkg audit reported issues, running dpkg --configure -a"
-  dpkg --configure -a || true
-fi
-
-apt-get update
-
-if ! apt-get $APT_OPTS upgrade; then
-  echo "upgrade failed, attempting apt-get -f install"
-  apt-get $APT_OPTS -f install
-  apt-get $APT_OPTS upgrade
-fi
-
-apt-get $APT_OPTS dist-upgrade
-apt-get $APT_OPTS autoremove --purge
-apt-get clean
-
-if [ -f /var/run/reboot-required ]; then
-  echo "REBOOT_REQUIRED=yes"
-  echo "REBOOT_REASON<<EOF"
-  cat /var/run/reboot-required.pkgs 2>/dev/null || echo "(no package list)"
-  echo "EOF"
-else
-  echo "REBOOT_REQUIRED=no"
-fi
-REMOTE
-
-  log "=== Phase D: apt complete (check REBOOT_REQUIRED in the log) ==="
-}
-
-# --------------------------------------------------------------------------- #
-# Phase E — Reboot cp-1 and wait for api-server /livez
-# --------------------------------------------------------------------------- #
-phase_reboot() {
-  log "=== Phase E: reboot $NODE ==="
-
-  # Tell cp-1 to reboot. The ssh command will hang up mid-command — that's fine.
-  if [ "$DRY_RUN" != "1" ]; then
-    log "issuing 'systemctl reboot' on $NODE (ssh will drop; expected)"
-    ssh $SSH_OPTS "root@$CP1_HOST" 'systemctl reboot' 2>&1 | tee -a "$LOG_LOCAL" || true
-    log "waiting 15s for ssh to fully drop before polling api-server"
-    sleep 15
-  else
-    log "DRY-RUN would ssh root@$CP1_HOST 'systemctl reboot'"
-  fi
-
-  log "-- poll api-server /livez (timeout ${REBOOT_MAX_WAIT_SECONDS}s)"
-  if [ "$DRY_RUN" != "1" ]; then
-    local deadline=$(( $(date +%s) + REBOOT_MAX_WAIT_SECONDS ))
-    local code=000
-    while [ $(date +%s) -lt $deadline ]; do
-      code=$(curl -sk -o /dev/null -w '%{http_code}' "https://$CP1_HOST:6443/livez" 2>/dev/null || echo 000)
-      if [ "$code" = "200" ]; then
-        log "  api-server /livez=200 (elapsed $(( REBOOT_MAX_WAIT_SECONDS - (deadline - $(date +%s)) ))s)"
-        break
-      fi
-      sleep 5
-    done
-    [ "$code" = "200" ] || die "api-server did not return within ${REBOOT_MAX_WAIT_SECONDS}s — escalate; check 'hcloud server describe k3s-cp-1' and Hetzner console"
-  fi
-
-  log "-- wait for kubelet Ready on $NODE (max 300s)"
-  if [ "$DRY_RUN" != "1" ]; then
-    local deadline=$(( $(date +%s) + 300 ))
-    local ready=Unknown
-    while [ $(date +%s) -lt $deadline ]; do
-      ready=$(kubectl get node "$NODE" -o jsonpath='{.status.conditions[?(@.type=="Ready")].status}' 2>/dev/null || echo Unknown)
-      [ "$ready" = "True" ] && break
-      sleep 5
-    done
-    [ "$ready" = "True" ] || die "kubelet on $NODE never returned Ready — escalate (do NOT change k3s config)"
-    log "  kubelet Ready=True"
-  fi
-
-  log "=== Phase E: cp-1 is back ==="
-}
-
-# --------------------------------------------------------------------------- #
-# Phase F — Uncordon + verify + finalize
-# --------------------------------------------------------------------------- #
-phase_finalize() {
-  log "=== Phase F: uncordon + verify ==="
-
-  run kubectl uncordon "$NODE"
-
-  log "-- settle wait ${POST_UNCORDON_WAIT_SECONDS}s"
-  [ "$DRY_RUN" = "1" ] || sleep "$POST_UNCORDON_WAIT_SECONDS"
-
-  log "-- cluster health"
-  if [ "$DRY_RUN" != "1" ]; then
-    if ! RETRY_ON_TRANSIENT=1 "$HEALTH_SCRIPT" 2>&1 | tee -a "$LOG_LOCAL"; then
-      die "cluster health failed after cp-1 update — escalate, do NOT touch k3s"
-    fi
-  fi
-
-  log "-- apt history summary (audit)"
-  ssh_run 'zgrep -h "Commandline\|Install\|Upgrade\|Remove" /var/log/apt/history.log* 2>/dev/null | tail -60'
-
-  log "-- old snapshots (>30d) — listing only, review manually"
-  ssh_run 'find /var/lib/rancher/k3s/server/db/snapshots/ -type f -mtime +30 -name "pre-*" -print 2>/dev/null || true'
-
-  log "=== cp-1 OS update complete — attach $LOG_LOCAL to the execution ticket ==="
-}
-
-# --------------------------------------------------------------------------- #
-# --run — orchestrate all phases with confirmations
-# --------------------------------------------------------------------------- #
-phase_run_all() {
-  log "=== full cp-1 update run (log: $LOG_LOCAL) ==="
-
-  confirm "Phase A (add swap) — proceed?"
-  phase_add_swap
-
-  confirm "Phase B (preflight) — proceed?"
-  phase_preflight
-
-  confirm "Phase C (cordon + batched stateful move) — proceed?"
-  phase_drain_stateful
-
-  confirm "Phase D (drain remaining + apt) — proceed?"
-  phase_apt
-
-  confirm "Phase E (reboot cp-1; api-server unavailable ~90-180s) — proceed?"
-  phase_reboot
-
-  confirm "Phase F (uncordon + verify) — proceed?"
-  phase_finalize
-
-  log "=== FULL RUN COMPLETE ==="
-}
-
-# --------------------------------------------------------------------------- #
-# Arg parse
-# --------------------------------------------------------------------------- #
-usage() { grep -E '^# ' "$0" | sed 's/^# \{0,1\}//'; exit 2; }
-
-[ $# -ge 1 ] || usage
-
-# Init the local log file up front so tee always has a target.
-: > "$LOG_LOCAL"
-log "update-cp-1.sh started (DRY_RUN=$DRY_RUN)"
-log "log file: $LOG_LOCAL"
-
-case "$1" in
-  --dry-run)
-    DRY_RUN=1
-    export DRY_RUN
-    log "DRY_RUN=1 — walking Phases A..F without touching state"
-    phase_add_swap
-    phase_preflight
-    phase_drain_stateful
-    phase_apt
-    phase_reboot
-    phase_finalize
-    ;;
-  --add-swap)       phase_add_swap ;;
-  --preflight)      phase_preflight ;;
-  --drain-stateful) phase_drain_stateful ;;
-  --apt)            phase_apt ;;
-  --reboot)         phase_reboot ;;
-  --finalize)       phase_finalize ;;
-  --run)            phase_run_all ;;
-  -h|--help)        usage ;;
-  *)                echo "unknown arg: $1" >&2; usage ;;
-esac