docs(access): implementation plan for ADR-021 operational access

Splits the work into Tranche A (land now: ADR-021, ADR-016/020
reconciliation, ssh-from-control firewall source, ACCESS.md template,
/check-access command, governance + index wiring) and Tranche B
(build-pending on infra: per-service access__* + rendered ACCESS.md,
/check-access running).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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# Operational Access (ADR-021) Implementation Plan
> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
**Goal:** Establish operational access as a deployment deliverable — a documented, verifiable set of mesh-reachable troubleshooting paths for every host and service — by writing ADR-021, reconciling the latent ADR-016/020 SSH contradiction, adding the control-node SSH source to the host firewall, and wiring the `ACCESS.md` record + `/check-access` verifier into boma's governance.
**Architecture:** Source of truth is the committed design spec `docs/superpowers/specs/2026-06-09-operational-access-design.md`. Structured access facts live as declarative `access__*` data that renders `ACCESS.md` and drives `/check-access` (the access analogue of `VERIFY.md` + `/verify-service`). Work is split into **Tranche A — land now** (doctrine docs, the one firewall code change, the dormant `/check-access` command, governance wiring) and **Tranche B — build-pending on infra** (per-service `access__*` population, rendered `ACCESS.md` files, and `/check-access` *running*), which arrive with service roles and live hosts and require no action in this plan.
**Tech Stack:** Markdown ADRs/docs; Ansible role `base` (Jinja2 nftables template + `defaults/main.yml`); Molecule (Debian 13, render + `nft -c`, no apply) for the firewall test; Claude Code command file for `/check-access`.
---
## File structure
| File | Tranche | Responsibility |
|---|---|---|
| `docs/decisions/021-operational-access.md` | A | NEW — the doctrine (two layers, three-tier ladder, break-glass, `access__*` model, `/check-access`) |
| `docs/decisions/016-mesh-vpn.md` | A | MODIFY — reconcile: SSH on `wt0` **and** from `ubongo`'s LAN address |
| `docs/decisions/020-firewall.md` | A | MODIFY — guaranteed management plane gains the control-node SSH source |
| `docs/access/service-access-template.md` | A | NEW — the `ACCESS.md` record shape (rendered-from-data + prose tail) |
| `roles/base/defaults/main.yml` | A | MODIFY — add `base__firewall_control_addr` knob (default empty → no-op) |
| `roles/base/templates/nftables.conf.j2` | A | MODIFY — conditional management-plane SSH rule for the control address |
| `roles/base/molecule/default/converge.yml` | A | MODIFY — set the knob for the test |
| `roles/base/molecule/default/verify.yml` | A | MODIFY — assert the rendered rule |
| `.claude/commands/check-access.md` | A | NEW — the `/check-access` verifier command (dormant until infra exists) |
| `docs/security/service-checklist.md` | A | MODIFY — one new gate item |
| `docs/runbooks/new-role.md` | A | MODIFY — new step: write `ACCESS.md` (mirrors SECURITY/VERIFY steps) |
| `CLAUDE.md` | A | MODIFY — `ACCESS.md` in Role conventions; ADR-021 in Further reading |
| `STATUS.md` | A | MODIFY — new rows for the doctrine, the firewall source, `/check-access` |
| `docs/TODO.md` | A | MODIFY — mark 3.2 + 7.2 DECIDED → ADR-021 |
**Tranche B (no tasks here — captured for the record):** per-service `access__*` blocks + rendered `roles/<svc>/ACCESS.md` land when each service role is built (governed by the Tranche-A checklist + runbook); `/check-access` *running* lands when `ubongo` + staging + vault exist. Both are designed-now, build-pending — exactly like `/verify-service` under ADR-017.
---
## Tranche A — Land now
### Task 1: Write ADR-021
**Files:**
- Create: `docs/decisions/021-operational-access.md`
The ADR is the durable decision record derived from the committed spec
`docs/superpowers/specs/2026-06-09-operational-access-design.md`. Match the prose style and
heading shape of an existing ADR (read `docs/decisions/020-firewall.md` first). The ADR
**must** state these specifics — they are the parts easy to get wrong:
- **Doctrine sentence (verbatim):** *"Every host and every service guarantees at least one
documented, verifiable way in for operational troubleshooting — and the deploy that
creates it also records and proves it."*
- **Two layers:** host baseline (resolves TODO 7.2) + per-service record (resolves TODO 3.2).
- **Three-tier access ladder:** (1) `wt0` mesh SSH — primary, WireGuard-authenticated;
(2) LAN SSH from `ubongo` only — secondary, mesh-independent, source-IP-gated **plus**
keys-only + fail2ban; all other LAN hosts stay default-denied; (3) console — break-glass
per host class: cluster VMs → Proxmox serial/VNC console, `askari` → Hetzner
rescue/console, `ubongo` → local console; reachability-checked, never exercised.
- **Reconciliation, not weakening (state this explicitly):** ADR-016 already requires
Ansible to reach the fleet by LAN IP ("a mesh/coordinator outage never blocks on-LAN
runs"), which *requires* LAN SSH from `ubongo`; yet ADR-016 also said "SSH only on `wt0`"
and ADR-020's guaranteed management plane listed only `wt0`. ADR-021 resolves that latent
contradiction by making the control-node SSH allow explicit and adding it to the
guaranteed management plane. It does **not** weaken default-deny: exactly one extra
trusted source on the LAN.
- **Declarative `access__*` data model:** service-role defaults carry `access__service`,
`access__compose_project`, `access__compose_path`, `access__containers`,
`access__log.loki_labels`, and `access__api` (`enabled`, `base_url`, `firewall_ref`,
`auth.vault_ref`, `health_path`; or `enabled: false` + `reason`). **Invariant:**
`access__api` never opens a port — it `firewall_ref`s the `group_vars` firewall catalog;
ADR-020 stays the sole owner of exposure.
- **Rendered record:** `ACCESS.md` is rendered from that data + a prose tail (operational
notes / gotchas). First-class sibling of `SECURITY.md`/`VERIFY.md`.
- **`/check-access`:** the verifier that probes each declared path and reports which are
live; break-glass reachability-only; designed now, build-pending on infra.
- **Status / consequences:** what lands now vs build-pending (mirror this plan's split).
- [ ] **Step 1: Author the ADR**
Write `docs/decisions/021-operational-access.md` covering every bullet above, in the
house style of `docs/decisions/020-firewall.md` (problem → decision → layers/ladder →
data model → verifier → consequences). Open with a one-line title heading
`# ADR-021 — Operational access: documented, verifiable ways in`.
- [ ] **Step 2: Sanity-check internal links**
Run: `grep -n "ADR-01[67]\|ADR-020\|access__\|check-access\|ACCESS.md" docs/decisions/021-operational-access.md`
Expected: references to ADR-016, ADR-020, the `access__*` keys, `/check-access`, and
`ACCESS.md` all present.
- [ ] **Step 3: Commit**
```bash
git add docs/decisions/021-operational-access.md
git commit -m "docs(access): add ADR-021 operational-access doctrine"
```
---
### Task 2: Reconcile ADR-016 and ADR-020
**Files:**
- Modify: `docs/decisions/016-mesh-vpn.md` (the "Host firewall" bullet, ~line 64-65)
- Modify: `docs/decisions/020-firewall.md` (the "Guaranteed management plane" bullet, ~line 42-45)
- [ ] **Step 1: Amend ADR-016's Host-firewall bullet**
Replace the existing bullet:
```markdown
- **Host firewall:** NetBird's `wt0` interface; `base` nftables allows inbound SSH
**only on `wt0`** (the ADR-015 pattern, fleet-wide).
```
with:
```markdown
- **Host firewall:** `base` nftables allows inbound SSH on NetBird's `wt0` interface
(primary, WireGuard-authenticated) **and** from `ubongo`'s LAN address (secondary,
mesh-independent — required by the LAN-IP recovery path below, so a mesh/coordinator
outage never blocks on-LAN SSH). All other LAN hosts remain default-denied. This makes
explicit the control-node SSH allow that the recovery model already implied; the access
doctrine and the three-tier access ladder live in **ADR-021**.
```
- [ ] **Step 2: Amend ADR-020's guaranteed-management-plane bullet**
Replace:
```markdown
- **Guaranteed management plane**: loopback, established/related, and `wt0` (NetBird,
ADR-016) for SSH + Ansible are always allowed, independent of the catalog, applied
atomically — a malformed or empty catalog can never lock out management. (ADR-016: SSH
is allowed only on `wt0`.)
```
with:
```markdown
- **Guaranteed management plane**: loopback, established/related, `wt0` (NetBird,
ADR-016), and SSH from the control node's LAN address (`base__firewall_control_addr`,
the `ssh-from-control` source) for SSH + Ansible are always allowed, independent of the
catalog, applied atomically — a malformed or empty catalog can never lock out
management. The control-node source is part of the guaranteed plane, not the service
catalog (it is management, not a service); see ADR-021 for the access doctrine.
```
- [ ] **Step 3: Commit**
```bash
git add docs/decisions/016-mesh-vpn.md docs/decisions/020-firewall.md
git commit -m "docs(access): reconcile ADR-016/020 with control-node SSH source (ADR-021)"
```
---
### Task 3: The `ACCESS.md` record template
**Files:**
- Create: `docs/access/service-access-template.md`
Match the preamble convention of `docs/security/service-security-template.md` and
`docs/testing/service-verify-template.md` (a "copy this to `roles/<service>/ACCESS.md`"
preamble, then a `---`, then the record).
- [ ] **Step 1: Write the template**
Create `docs/access/service-access-template.md`:
```markdown
# Per-service operational-access record — template
Copy this file to `roles/<service>/ACCESS.md` when building a service role (ADR-021).
It is the per-service **operational-access record**: every documented, verifiable way in
for troubleshooting. The structured parts are **rendered from the role's `access__*`
data** (the single source of truth that also drives `/check-access`) — keep the data
authoritative and regenerate this file rather than hand-editing the tables. The prose
"Operational notes" tail is hand-written.
Delete this preamble in the copy and start from the heading below.
---
# Access — <service>
## Access paths
The mesh-reachable ways in, by tier (rendered from `access__*`):
| Tier | Path | Invocation |
|---|---|---|
| primary | `wt0` mesh SSH | `ssh <host>` (over the NetBird mesh) |
| secondary | LAN SSH from `ubongo` | `ssh <host>` (from the control node, LAN address) |
| — | container exec + compose | `docker compose -p <access__compose_project> -f <access__compose_path> ps` / `exec` |
| — | logs | Loki query for labels `<access__log.loki_labels>` (Grafana; ADR-018) |
| — | admin API | `curl -H 'Authorization: …(vault_ref)' <access__api.base_url><health_path>` — or `n/a` |
## Break-glass
Mesh-and-LAN-independent fallback for this host's class (recorded, not routine):
- <Proxmox serial/VNC console for cluster VMs · Hetzner rescue for `askari` · local console for `ubongo`>
## Operational notes
Prose the data can't capture — service quirks, "if X is wedged, do Y", ordering gotchas.
- <none yet>
```
- [ ] **Step 2: Commit**
```bash
git add docs/access/service-access-template.md
git commit -m "docs(access): add ACCESS.md service record template"
```
---
### Task 4: Add the control-node SSH source to the host firewall (TDD)
**Files:**
- Modify: `roles/base/defaults/main.yml`
- Modify: `roles/base/templates/nftables.conf.j2`
- Modify: `roles/base/molecule/default/converge.yml`
- Modify: `roles/base/molecule/default/verify.yml`
This is the only code in Tranche A. It adds an **optional** guaranteed-management-plane
allow for SSH from the control node's LAN address. Default empty ⇒ no rule rendered ⇒
no behaviour change until a real `ubongo` address is set in `group_vars` (build-pending).
Test path is the established one for this role: Molecule render + `nft -c` (no apply).
- [ ] **Step 1: Write the failing test — converge sets the knob, verify asserts the rule**
In `roles/base/molecule/default/converge.yml`, add the knob under `vars:` (alongside
`base__firewall_apply: false`):
```yaml
base__firewall_control_addr: 10.10.0.99 # test control-node LAN address
```
In `roles/base/molecule/default/verify.yml`, extend the "management plane" assert block's
`that:` list (the task asserting default-deny + `wt0` SSH) with:
```yaml
- "'ip saddr 10.10.0.99 tcp dport 22 accept' in nft"
```
- [ ] **Step 2: Run the test to verify it fails**
Run: `make test ROLE=base`
Expected: FAIL — the verify assert "input chain is missing default-deny or the management
plane" fires, because the template does not yet render the control-address rule.
- [ ] **Step 3: Add the default knob**
In `roles/base/defaults/main.yml`, after the `base__firewall_mgmt_interface` line, add:
```yaml
base__firewall_control_addr: "" # control-node LAN address (ubongo); SSH allowed from it
# as the guaranteed-management-plane `ssh-from-control`
# source (ADR-021). Empty = no rule. Set in group_vars
# once ubongo exists.
```
- [ ] **Step 4: Render the rule in the template**
In `roles/base/templates/nftables.conf.j2`, immediately after the `wt0` SSH line (the
`iifname "{{ base__firewall_mgmt_interface }}" ...` line), add:
```jinja
{% if base__firewall_control_addr %}
ip saddr {{ base__firewall_control_addr }} tcp dport {{ base__firewall_ssh_port }} accept
{% endif %}
```
- [ ] **Step 5: Run the test to verify it passes**
Run: `make test ROLE=base`
Expected: PASS — the rule `ip saddr 10.10.0.99 tcp dport 22 accept` renders, `nft -c`
syntax-check succeeds, and all prior assertions (default-deny, `wt0` SSH, zone rules,
drop-in hook) still pass.
- [ ] **Step 6: Lint**
Run: `make lint`
Expected: PASS (no tag/FQCN/yaml regressions).
- [ ] **Step 7: Commit**
```bash
git add roles/base/defaults/main.yml roles/base/templates/nftables.conf.j2 \
roles/base/molecule/default/converge.yml roles/base/molecule/default/verify.yml
git commit -m "feat(base): add ssh-from-control management-plane source (ADR-021)"
```
---
### Task 5: Author the `/check-access` command (dormant until infra)
**Files:**
- Create: `.claude/commands/check-access.md`
Mirror the structure of `.claude/commands/verify-service.md` (a forward-looking command
with a hard Prerequisites gate). It does not run until `ubongo` + live/staging hosts +
vault exist; if a prerequisite is missing it must say so and stop.
- [ ] **Step 1: Write the command**
Create `.claude/commands/check-access.md`:
```markdown
Operational-access verification (ADR-021)
Probe every documented way in to a service or host from `ubongo` and report which paths
are live. Reads the target's `access__*` data (and host baseline), so the verifier and
`ACCESS.md` can never disagree. Argument: a service/role name or a host
(e.g. `/check-access photoprism`, `/check-access docker01`).
## Prerequisites (forward-looking — ADR-021 dependencies)
This skill cannot run until these exist; if any is missing, say so and stop — do not
improvise around it:
- `ubongo` reachable on the mesh **and** the LAN (it runs the probes).
- The target host/service is deployed (staging or production inventory).
- `roles/<name>/` carries `access__*` data (services) / the host baseline applies.
- Vault unlocked (`rbw unlocked`) for any token-authenticated API probe.
## Process
### Phase 0 — resolve the target
Resolve the argument to a host or a service role + its host. Load the `access__*` data
(service) or the host-baseline + break-glass record (host). State what you will probe.
### Phase 1 — probe each declared path
| Path | Probe | Green = |
|---|---|---|
| `wt0` mesh SSH | connect over the mesh, run `true` | reachable + key works |
| LAN SSH from `ubongo` | connect via the LAN address, run `true` | reachable + key works |
| exec + compose | `docker compose -p <project> ps`; exec `true` in each `access__containers` entry | stack up, exec works |
| logs | query Loki for `access__log.loki_labels`, expect recent lines | logs flowing |
| admin API | `curl` `access__api.health_path` with the token from `access__api.auth.vault_ref` | 2xx |
| break-glass | reachability of the Proxmox/provider console endpoint **only** | console host reachable |
Break-glass is **never exercised** — firing a serial console is invasive; confirm the
fallback exists, do not drive it.
### Phase 2 — report
Emit a pass/fail table. For any red path, name it and the likely cause (e.g. "API token
in vault stale", "Alloy not shipping", "`base__firewall_control_addr` unset → no
`ssh-from-control` rule"). Verdict line: e.g. "3/4 paths green; admin API red".
## Notes
- Read-only and non-destructive — probes confirm reachability, they do not change state.
- This is the access analogue of `/verify-service` (ADR-017): designed now, runs when the
control node + hosts exist.
```
- [ ] **Step 2: Commit**
```bash
git add .claude/commands/check-access.md
git commit -m "feat(access): add /check-access verifier command (ADR-021, dormant)"
```
---
### Task 6: Governance wiring — checklist + runbook
**Files:**
- Modify: `docs/security/service-checklist.md` (the "Operability (security-adjacent)" section)
- Modify: `docs/runbooks/new-role.md` (after step 10, the VERIFY.md step)
ACCESS.md mirrors how SECURITY.md/VERIFY.md are enforced: a manual runbook step + a
checklist gate (the scaffold does not auto-drop SECURITY/VERIFY today either, so ACCESS
follows the same manual-copy pattern — no Makefile change).
- [ ] **Step 1: Add the checklist gate item**
In `docs/security/service-checklist.md`, under `## Operability (security-adjacent)`, add a
bullet after the `/verify-service` item:
```markdown
- [ ] Operational access recorded and verifiable (ADR-021): the role carries `access__*`
data, `roles/<service>/ACCESS.md` is rendered, and `/check-access` reports the
documented paths green — or a deviation is recorded in
`docs/security/accepted-risks.md`
```
- [ ] **Step 2: Add the runbook step**
In `docs/runbooks/new-role.md`, insert a new step between step 10 (VERIFY.md) and the
final commit step, and renumber the commit step to 12:
```markdown
### 11. Write the per-service operational-access record (services)
For a **service** role, copy `docs/access/service-access-template.md` to
`roles/<rolename>/ACCESS.md` and populate the role's `access__*` data
(`access__service`, `access__compose_project`/`_path`, `access__containers`,
`access__log.loki_labels`, and `access__api``enabled` + endpoint + `firewall_ref` +
`auth.vault_ref` + `health_path`, or `enabled: false` with a reason). `ACCESS.md` is
rendered from that data; the admin-API path must `firewall_ref` an entry in the
`group_vars` firewall catalog, never open a port itself (ADR-020/021). Once hosts exist,
`/check-access <rolename>` proves the documented paths are live — part of the
service-clearance gate (`docs/security/service-checklist.md`).
```
- [ ] **Step 3: Verify renumbering**
Run: `grep -n "^### 1[12]\." docs/runbooks/new-role.md`
Expected: `### 11. Write the per-service operational-access record` and `### 12. Commit`.
- [ ] **Step 4: Commit**
```bash
git add docs/security/service-checklist.md docs/runbooks/new-role.md
git commit -m "docs(access): gate ACCESS.md in checklist + new-role runbook (ADR-021)"
```
---
### Task 7: Index wiring — CLAUDE.md, STATUS.md, TODO.md
**Files:**
- Modify: `CLAUDE.md` (Role conventions list + Further reading table)
- Modify: `STATUS.md` (Designed-but-not-built table)
- Modify: `docs/TODO.md` (items 3.2 and 7.2)
- [ ] **Step 1: CLAUDE.md — Role conventions**
In the `## Role conventions` list, after the `VERIFY.md` bullet
("Every **service** role must have a populated `VERIFY.md` ..."), add:
```markdown
- Every **service** role must have a populated `ACCESS.md` (ADR-021) — copy
`docs/access/service-access-template.md`; rendered from the role's `access__*` data
```
- [ ] **Step 2: CLAUDE.md — Further reading**
In the Further reading table, after the Firewall strategy row, add:
```markdown
| Operational access | `docs/decisions/021-operational-access.md` |
```
- [ ] **Step 3: STATUS.md — new rows**
In the `## Designed but not built` table, add:
```markdown
| Operational-access doctrine (ADR-021) | ADR-021 | **Design RESOLVED** (ADR-021 + spec + plan). Two-layer doctrine, three-tier access ladder, `access__*` model, `ACCESS.md` record, `/check-access`. Reconciles ADR-016/020 SSH. |
| `ssh-from-control` firewall source | ADR-021 / ADR-020 | **Built (dormant).** `base__firewall_control_addr` knob + nftables rule + Molecule assertion landed; empty default = no rule until `ubongo`'s LAN address is set in `group_vars`. |
| `/check-access` verifier | ADR-021 | **Design RESOLVED** (`.claude/commands/check-access.md` authored). **Build pending:** running needs `ubongo` + live/staging hosts + vault. Access analogue of `/verify-service` (ADR-017). |
| Per-service `ACCESS.md` records | ADR-021 | Template + governance present; per-service files render when each service role is built. |
```
- [ ] **Step 4: docs/TODO.md — mark 3.2 and 7.2 DECIDED**
In `docs/TODO.md`, change item **3.2** from:
```markdown
2. Decide how to manage APIs / API access.
```
to:
```markdown
2. ~~Decide how to manage APIs / API access.~~ DECIDED (ADR-021): per-service `access__*`
data declares the admin API (endpoint + `firewall_ref` to the catalog + vault token
ref + health path); rendered into `ACCESS.md` and probed by `/check-access`. Part of
the two-layer operational-access doctrine.
```
And change item **7.2** from:
```markdown
2. Decide what to set up on the hosts, given that direct access will be rare.
```
to:
```markdown
2. ~~Decide what to set up on the hosts, given that direct access will be rare.~~
DECIDED (ADR-021): the host-layer access baseline — SSH on `wt0` + from `ubongo`,
Docker/Compose tooling, Alloy log shipping, and a recorded break-glass console per
host class.
```
- [ ] **Step 5: Verify and commit**
Run: `grep -n "021-operational-access\|ACCESS.md\|ssh-from-control" CLAUDE.md STATUS.md`
Expected: the new Role-conventions bullet, the Further-reading row, and the STATUS rows
are present.
```bash
git add CLAUDE.md STATUS.md docs/TODO.md
git commit -m "docs(access): wire ADR-021 into CLAUDE.md, STATUS, TODO"
```
---
## Tranche B — Build-pending on infra (no tasks now)
Recorded so the boundary is explicit; nothing here is actioned by this plan.
- **Per-service `access__*` + rendered `ACCESS.md`** — authored when each service role is
built, governed by the Task 6 checklist item + runbook step. The first real service role
is where this first runs.
- **`/check-access` running** — needs `ubongo` + a live/staging host + vault. The command
(Task 5) already gates on these and stops cleanly until then.
- **Real `base__firewall_control_addr` value** — set in `group_vars/all` to `ubongo`'s LAN
address once `ubongo` is in inventory; the machinery + test landed in Task 4.
---
## Self-review
**Spec coverage:** doctrine + two layers → Task 1; three-tier ladder + ADR-016/020
reconciliation → Tasks 12, 4; `access__*` model + invariant → Tasks 1, 3, 6; rendered
`ACCESS.md` → Task 3; `/check-access` → Task 5; governance (checklist/runbook) → Task 6;
repo wiring (CLAUDE/STATUS/TODO) → Task 7; build-now vs build-pending split → Tranches
A/B. All spec sections map to a task.
**Deviations from the spec (deliberate, flagged for the user):**
1. The spec called `ssh-from-control` a *catalog* source; the plan places it in the
*guaranteed management plane* (`base__firewall_control_addr`) instead — ADR-020 already
houses SSH/Ansible management allows there, independent of the catalog, and the spec's
own invariant says the catalog owns *service* exposure only. Same intent, correct home.
2. The spec said `make new-role` would *scaffold* an `ACCESS.md` stub; the plan instead adds
a manual runbook step (Task 6) mirroring how `SECURITY.md`/`VERIFY.md` are handled today
(also manual copies, not scaffolded). Avoids unilaterally restructuring the scaffold;
the "can't be forgotten" intent is met by the checklist gate + runbook step.
**Type/name consistency:** `base__firewall_control_addr` (knob), `access__service` /
`access__compose_project` / `access__compose_path` / `access__containers` /
`access__log.loki_labels` / `access__api.{enabled,base_url,firewall_ref,auth.vault_ref,health_path}`
are used identically across Tasks 1, 3, 5, 6. The rendered nftables rule string
`ip saddr <addr> tcp dport 22 accept` matches between Task 4's template (Step 4) and its
assertion (Step 1).