# SPIKE — controller↔agent TLS leaf-pin mismatch (disk ops + quiesce backup dead) - **Date:** 2026-06-29 - **Class:** Diagnostic / read-only. **No code, config, cert, service, or version change was made.** - **Host:** felhom-pve (`demo-felhom`, 192.168.0.162), controller in **LXC 9201**. - **Verdict:** **Hypothesis #1 — the agent local-API leaf was regenerated** during the root→non-root agent migration on **2026-06-28 ~08:56 CEST**. The controller's pin (and `bootstrap.json` seed) still reference the **pre-migration** leaf. A secondary blocker (empty token store) is latent behind the pin and will surface the moment the pin is fixed. - **RESOLVED 2026-06-29 via R1** (RUNBOOK, supervised) — service restored; see the closing **§9 Outcome** at the bottom. --- ## 1. Live running versions | Component | Version / image | Notes | |---|---|---| | Host agent | **felhom-agent 0.43.0** | unit `felhom-agent.service`, runs **non-root** as `felhom-agent`, `--config /etc/felhom-agent/agent.json`, `ActiveEnterTimestamp = Sun 2026-06-28 08:59:06 CEST` | | In-guest controller | **felhom-controller:0.89.0** | LXC 9201, `Up ~1h (healthy)` at probe time | --- ## 2. The three fingerprints | Label | Value | Source | |---|---|---| | **AGENT_FP** (served now) | `ced34036440639f48f4b96fb1802e79b2c1b3102eb763d3ba97aea2da1944f9c` | on-disk `local-api.crt` **==** live wire (`s_client`) **==** boot log — all three agree | | **PIN_FP** (controller pins) | `60b5974d586f5f3c8ec41eb998d0f07406178219c36bf6d3ff377570279d8245` | `controller.yaml → local_api.fingerprint` (data volume in 9201) | | **SEED_FP** (bootstrap seed) | `60b5974d586f5f3c8ec41eb998d0f07406178219c36bf6d3ff377570279d8245` | `/etc/felhom-bootstrap/bootstrap.json → local_api.fingerprint` | `PIN_FP == SEED_FP == 60b5974d…` ≠ `AGENT_FP == ced34036…`. The controller is talking to the **right endpoint** (both sides `192.168.0.162:8443`) and pinning a **consistent but now-obsolete** leaf. --- ## 3. Raw evidence ### A — what the agent serves (host felhom-pve) **A1 — socket owner on :8443** (single process, not a stale/second daemon → hypothesis #3 ruled out): ``` LISTEN 192.168.0.162:8443 users:(("felhom-agent",pid=3550072,fd=18)) ``` **A2 — unit + boot-log fingerprint history.** The leaf fingerprint logged at every boot is stable `60b5974d…` from Jun 24 through Jun 27, then **flips to `ced34036…` on Jun 28 08:56:37**, same cert path: ``` Jun 26 19:54:50 local-api leaf ready fingerprint_sha256=60b5974d… cert=/var/lib/felhom-agent/local-api.crt Jun 27 … (controller swaps to 0.86.0 / 0.87.0; leaf still 60b5974d) Jun 28 08:56:37 local-api leaf ready fingerprint_sha256=ced34036… cert=/var/lib/felhom-agent/local-api.crt ← REGENERATED Jun 28 08:59:06 local-api leaf ready fingerprint_sha256=ced34036… cert=/var/lib/felhom-agent/local-api.crt ← current daemon (pid 3550072) ``` `ExecStart=/usr/local/bin/felhom-agent --config /etc/felhom-agent/agent.json`, `FragmentPath=/etc/systemd/system/felhom-agent.service`, `ActiveEnterTimestamp=2026-06-28 08:59:06`. **A3 — on-disk leaf** (fresh, owned by the new non-root user, mtime = the switchover): ``` -rw-r--r-- 1 felhom-agent felhom-agent 591 Jun 28 08:56 local-api.crt -rw------- 1 felhom-agent felhom-agent 227 Jun 28 08:56 local-api.key -rw------- 1 felhom-agent felhom-agent 0 Jun 28 08:56 local-tokens.log ← 0 bytes (see §6) openssl … DER | sha256sum = ced34036440639f48f4b96fb1802e79b2c1b3102eb763d3ba97aea2da1944f9c serial=85131255A9AE3FD902A5DB12A15D0459 notBefore=Jun 28 05:56:37 2026 GMT notAfter=Jun 25 05:56:37 2036 GMT ``` **A4 — on-the-wire leaf** (live `s_client` to 192.168.0.162:8443): ``` ced34036440639f48f4b96fb1802e79b2c1b3102eb763d3ba97aea2da1944f9c ``` → **wire == disk == boot-log.** No stale/second process; one honest agent serving one fresh cert. **A5 — agent config `local_api`** (paths NOT overridden to anything unexpected; defaults): ```json "local_api": { "enable": true, "listen_addr": "192.168.0.162:8443", "cert_file": "/var/lib/felhom-agent/local-api.crt", "key_file": "/var/lib/felhom-agent/local-api.key", "token_store": "/var/lib/felhom-agent/local-tokens.log" } ``` **Surviving pre-migration leaf (the restore candidate).** A set-aside copy of the old root-era `/var/lib` exists from the bundle migration test, and it **matches the controller pin exactly**: ``` /root/agent-backup-bundle-test/aside-var-lib/local-api.crt DER|sha256 = 60b5974d586f5f3c8ec41eb998d0f07406178219c36bf6d3ff377570279d8245 ← == PIN_FP == SEED_FP notBefore=Jun 10 06:52:37 2026 GMT serial=8FFA15857DABD903BB53742E6EA2CE46 (local-api.key present alongside) ``` ### B — what the controller pins (LXC 9201) **B1 — `controller.yaml` `local_api`** (`/var/lib/docker/volumes/felhom-controller-data/_data/controller.yaml`): ```yaml local_api: endpoint: 192.168.0.162:8443 fingerprint: 60b5974d586f5f3c8ec41eb998d0f07406178219c36bf6d3ff377570279d8245 token: ``` **B2 — `bootstrap.json` seed** (`/etc/felhom-bootstrap/bootstrap.json`): ```json "local_api": { "endpoint": "192.168.0.162:8443", "fingerprint": "60b5974d586f5f3c8ec41eb998d0f07406178219c36bf6d3ff377570279d8245" } ``` **B3 — controller error log** (every 5 min, two distinct call sites): ``` [quiesce] cycle error: check due: agentapi: GET /backup/due: … TLS pin mismatch: agent leaf SHA-256 does not match the bootstrap fingerprint [web] disk list via agent failed: agentapi: GET /disks: … TLS pin mismatch: agent leaf SHA-256 does not match the bootstrap fingerprint ``` ### C — endpoint sanity `controller.yaml.endpoint` = `bootstrap.json.endpoint` = `agent listen_addr` = `192.168.0.162:8443`. The controller pins the right host; only the leaf value is stale. Endpoint mismatch ruled out. --- ## 4. Cert-regeneration ↔ agent-restart correlation The fresh leaf's `notBefore` (Jun 28 05:56:37 GMT = **08:56:37 CEST**, with the code's −1h skew backdate) and the cert/key mtimes (Jun 28 08:56) coincide to the second with the first post-migration `leaf ready` log line. The agent then settled into its current daemon at 08:59:06. This is **not** an expiry event (10-year validity) — it is `EnsureLeaf` taking the *generate* branch because the non-root agent's data dir (`/var/lib/felhom-agent`, now owned `felhom-agent:felhom-agent`) contained **no** cert/key at first boot under the new user. The old pair was preserved only in the `/root/agent-backup-bundle-test/aside-var-lib/` set-aside, so `EnsureLeaf` minted a new self-signed leaf and persisted it — changing the served fingerprint out from under every already-issued pin. This is a direct side-effect of the **BUNDLE Day-0 / root→non-root agent migration on 2026-06-28**. --- ## 5. Listening-socket owner Single process: `felhom-agent` pid **3550072** (the running daemon), bound to `192.168.0.162:8443`. No second/stale listener. Hypothesis #3 (stale process serving an old cert) is **disproven** — and note the *direction* is the opposite of #3 anyway: the live process serves the **new** cert, while the **old** value is the one frozen in the controller's pin. --- ## 6. Matched matrix row + conclusion Matrix row **#1 — agent leaf regenerated** (files were absent at the new non-root path; not a path typo, not an expiry): > A3 == A2 == fresh mtime (cert regenerated 2026-06-28 ~08:56, the agent redeploy/non-root switch); > `PIN_FP` ≠ `AGENT_FP`; a surviving backup cert matching `PIN_FP` **does** exist > (`…/aside-var-lib/`, fp `60b5974d…`). **Root cause (high confidence):** the root→non-root agent migration on 2026-06-28 reinitialised `/var/lib/felhom-agent` without carrying over the existing leaf, so the agent generated a new self-signed local-API leaf (`ced34036…`). The in-guest controller (and its `bootstrap.json`) still pin the pre-migration leaf (`60b5974d…`), so the pinned `agentapi` client fails closed on every call. Because **all** disk/storage/backup traffic goes through that one pinned client, both the disk UI **and** the quiesce app-consistent-backup loop are down. **Note — this is NOT a stale controller re-merge (#2).** `PIN_FP == SEED_FP`, so re-running the controller's bootstrap/`ensureLocalAPI` merge would re-apply the **same obsolete** `60b5974d…` and not help. The divergence originated on the agent side, not from a stale seed re-merge. ### Secondary blocker (latent behind the pin) — empty token store `/var/lib/felhom-agent/local-tokens.log` is **0 bytes**, mtime **2026-06-28 08:56** (reset at the same migration). The controller's per-guest bearer token was minted into the *pre-migration* store. The TLS pin fails first (handshake), so this is currently masked — but once the pin is corrected the agent will have **no token entry** for guest 9201 and authenticated calls will **401**. This matches the known "local-API 401 until token re-seed after agent restart / stale token map" pattern. **Any remedy below must be paired with re-seeding the guest token** (re-provision token mint, or restore the old token store), or the symptom merely changes from `TLS pin mismatch` to `401`. --- ## 7. Remedy options for the operator (NOT executed — operator's choice) | # | Remedy | Effect | Trade-offs / cautions | |---|---|---|---| | **R1** | **Restore the pre-migration leaf**: copy `…/aside-var-lib/local-api.{crt,key}` → `/var/lib/felhom-agent/`, `chown felhom-agent:felhom-agent`, `0644/0600`, restart agent | Agent serves `60b5974d…` again → matches existing `PIN_FP`+`SEED_FP`; **zero controller-side change** | Lowest blast radius. Verify the **non-root** user can read both files; restart now *loads* (files present) so it mints nothing new. Does **not** fix the token store. | | **R2** | **Re-pin the controller** to `ced34036…`: set `controller.yaml.local_api.fingerprint` (and `bootstrap.json`) to AGENT_FP, restart controller | Keeps the freshly-generated leaf; controller trusts the current agent | Edits in-guest config; keeps the "current cert" as canonical, which is the cleaner long-term state if the migration intends a new leaf. Does **not** fix the token store. | | **R3** | **Re-bootstrap / re-provision the controller** against the live agent | Re-mints token **and** re-pins fingerprint from a freshly emitted `bootstrap.json` | Heaviest; resolves the token-store blocker too — but only correct if a fresh `bootstrap.json` carrying AGENT_FP is generated (the *existing* one still holds the stale `60b5974d…` and must be regenerated, not reused). | **Token store (applies to R1/R2):** also re-seed guest 9201's bearer token into `/var/lib/felhom-agent/local-tokens.log` (re-provision token mint, or restore the old token store from the same `aside-var-lib` set-aside), else expect a `401` after the pin is fixed. ### Follow-up CONFIRMED (2026-06-29) — `aside-var-lib` holds the matching token store → R1 is one copy The set-aside **does** contain the pre-migration token store, and it matches guest 9201's *current* controller token, so **R1 fixes the pin and the token blocker in a single restore**: ``` /root/agent-backup-bundle-test/aside-var-lib/local-tokens.log 656 bytes, 8 records, mtime 2026-06-26 19:56 (pre-migration) effective (last-write-wins) vmids: 9200, 9201 vs live /var/lib/felhom-agent/local-tokens.log : 0 bytes, mtime 2026-06-28 08:56 (reset at migration) ``` Verified on-host (token plaintext/hashes never left the host; only the verdict was emitted): the agent stores `{"v":,"h":hex(sha256(token))}` JSONL (`internal/localapi/tokenstore.go`, last-write-wins per vmid). The SHA-256 of the controller's **current** `controller.yaml` `local_api.token` (the line under `local_api:`, **not** the unrelated `git:`/`hub:` tokens in the same file) is **present in the old store under vmid 9201**. So: - old leaf fp `60b5974d…` **==** `PIN_FP` (and `SEED_FP`) ✓ - old store's effective 9201 token hash **==** controller's current `local_api.token` hash ✓ **Therefore the cleanest remedy is R1 extended to three files:** restore `local-api.crt`, `local-api.key`, **and** `local-tokens.log` from `…/aside-var-lib/` → `/var/lib/felhom-agent/`, `chown felhom-agent:felhom-agent` (crt `0644`, key/tokens `0600`), restart the agent. The agent then *loads* (not regenerates) the old leaf and re-indexes the old token store; the controller's existing pin **and** token both validate, **with zero in-guest change**. (Caveat: this reinstates the pre-migration leaf `60b5974d…` rather than adopting the new `ced34036…` — fine for restoring service; if the operator wants the new leaf to be canonical, that's R2/R3 instead, both of which still need the token re-seed handled separately.) **Forward-looking:** the root→non-root migration runbook should **carry the existing `local-api.{crt,key}` and `local-tokens.log` into the new data dir** (or treat their loss as a re-bootstrap trigger). Regenerating the leaf silently invalidates every issued pin — exactly this incident. --- ## 8. Confidence + gaps - **Pin root cause: very high.** Disk == wire == boot-log all agree; mtime/`notBefore` pin the regeneration to the migration minute; the matching pre-migration backup leaf proves the old value. - **Token-store secondary blocker: high (inferred, not yet triggered).** The 0-byte store at the migration mtime is strong evidence; not *proven* live because the TLS pin fails before any token is evaluated, and probing it would require an authenticated call (out of scope for read-only). Operator should expect it and plan the token re-seed alongside whichever pin remedy is chosen. - **Resolved (was "not assessed"):** `…/aside-var-lib/` **does** hold the matching pre-migration `local-tokens.log`, and its effective 9201 token hash equals the controller's current `local_api.token` hash — so R1 restored as three files (crt+key+tokens) fixes pin **and** token in one copy, zero in-guest change. See §7 follow-up. *No secrets recorded: the per-guest bearer token is referenced as "stored out-of-band"; the leaf fingerprint is not a secret.* --- ## 9. Outcome — R1 executed 2026-06-29 (supervised), service RESTORED Ran the R1 RUNBOOK (restore the pre-migration leaf **+** token store from `/root/agent-backup-bundle-test/aside-var-lib/` → `/var/lib/felhom-agent/`, chown `felhom-agent`, modes 644/600/600, agent restart). Current post-migration state was first backed up to `/root/agent-rollback-20260629-150137/` (rollback source, retained). **Gates — all passed:** - **Gate 1 (loaded, not regenerated):** boot log `local-api leaf ready fingerprint_sha256=60b5974d…` at 15:02:10 — the agent **loaded** the restored leaf (ownership/mode correct; no third cert minted). - **Gate 2 (wire):** single `felhom-agent` listener on `192.168.0.162:8443`; on-wire leaf fp `60b5974d…` == controller `PIN_FP`. - **Gate 3 (real pinned+auth path):** authenticated `GET /disks` with the controller's `local_api.token` → **HTTP 200, ok=true, 5 disks**; a bogus token → **401** (auth genuinely enforced). Token/hashes never left the host. - **Controller corroboration:** the first quiesce cycle after the restart (15:05:33 CEST) succeeded end-to-end — *"backup due — quiescing 5 stack(s) … backup job … started … snapshotted — resuming app early … unquiescing: restarting 5 stack(s)"*. **No** `TLS pin mismatch` / 401 lines after 15:02. The disk UI path and the quiesce app-consistent-backup loop are both restored. **Restored values:** agent now serves leaf `60b5974d…` (matches the in-guest pin and `bootstrap.json` seed) and re-indexed the pre-migration token store (effective 9201 token = the controller's current `local_api.token`). **Zero in-guest change** was needed. **Retained (do not delete yet):** `/root/agent-backup-bundle-test/aside-var-lib/` (only copy of the pinning material until the future-proofing fix lands) and `/root/agent-rollback-20260629-150137/` (R1 rollback point). **Still open (carried forward, NOT addressed by R1):** - The root→non-root agent migration **regenerates the local-API leaf** (and truncates the token store) because it does not carry `local-api.{crt,key}` + `local-tokens.log` into the new `felhom-agent`-owned data dir. Until the migration/Day-0 path preserves these (or treats their loss as a re-bootstrap trigger), any re-migration/host-reprovision will reintroduce this exact mismatch. This restore reinstated the **old** leaf; it did not change the migration behavior.