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| author | Craig Jennings <c@cjennings.net> | 2026-07-11 00:54:56 -0500 |
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| committer | Craig Jennings <c@cjennings.net> | 2026-07-11 00:54:56 -0500 |
| commit | 0f7c166e1383286ee4117d16b5810814266ca02b (patch) | |
| tree | ef67e0ccd1ba8e1cb66e97b65bbc3f905a83bb7d /docs/specs/2026-07-11-net-doctor-expansion-spec.org | |
| parent | bd9091adb15bdbd5a0dc6b553adce8cb7098b97f (diff) | |
| download | archsetup-0f7c166e1383286ee4117d16b5810814266ca02b.tar.gz archsetup-0f7c166e1383286ee4117d16b5810814266ca02b.zip | |
docs: catalogue net + bt failure modes and draft two doctor expansion specs
I ran the audio doctor's design arc for the net and bluetooth doctors: a blind by-layer research catalogue of failure modes, a symptom-cluster triage, then a spec per doctor.
The taxonomy holds ~74 network and ~55 bluetooth distinct root causes, each sourced to a forum or issue-tracker report, sorted into eight network and five bluetooth symptom clusters. The clusters are keyed to each doctor's existing probe ladder, so the fix-versus-guide boundary falls along the tiers the doctor already walks. Every entry carries a remedy class (auto, privileged, reboot-tail, or guide), reusing the audio doctor's four-class run-time privilege model.
The two specs are expansions, not rewrites. The net doctor is already the most mature of the three: its classifier reaches six of the eight clusters today, so its spec adds only the control-plane cluster (a rival network manager, a masked NetworkManager, a bad keyfile) and sharper auth naming. The bt doctor's chain is structurally right but blind at both ends, so its spec adds a probe that names the firmware blob the kernel already logged and a probe that catches an adapter that power-on won't keep on across reboots. Both stay DRAFT with three open decisions each, headed for spec-review.
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diff --git a/docs/specs/2026-07-11-net-doctor-expansion-spec.org b/docs/specs/2026-07-11-net-doctor-expansion-spec.org new file mode 100644 index 0000000..aed22b8 --- /dev/null +++ b/docs/specs/2026-07-11-net-doctor-expansion-spec.org @@ -0,0 +1,197 @@ +#+TITLE: Net Doctor Expansion — the clusters the ladder doesn't yet name +#+AUTHOR: Craig Jennings +#+DATE: 2026-07-11 +#+TODO: TODO | DONE +#+TODO: DRAFT READY DOING | IMPLEMENTED SUPERSEDED CANCELLED + +* DRAFT Net Doctor Expansion +:PROPERTIES: +:ID: ce29b103-ed9d-4f56-bf8c-9ed8fe680ff3 +:END: +- [2026-07-11 Sat @ 00:08:41 -0500] DRAFT — drafted. Extends the existing net doctor (=~/.dotfiles/net/=, shipped) using the network half of the failure taxonomy ([[file:../design/2026-07-10-net-bt-failure-taxonomy.org][2026-07-10-net-bt-failure-taxonomy.org]]). Grounded in a read of the live engine, not memory. + +* Metadata + +| Field | Value | +|----------+-----------------------------------------------------------------------------------| +| Status | draft | +|----------+-----------------------------------------------------------------------------------| +| Owner | Craig Jennings | +|----------+-----------------------------------------------------------------------------------| +| Reviewer | Craig Jennings | +|----------+-----------------------------------------------------------------------------------| +| Related | [[file:../design/2026-07-10-net-bt-failure-taxonomy.org][net/bt failure taxonomy]] ; the cross-panel run-time-privilege and copy+close tasks | +|----------+-----------------------------------------------------------------------------------| + +* Summary + +The net doctor is the most mature of the three panel doctors: its probe ladder already walks link → IP → gateway → route → DNS → egress, and its classifier already names most of the taxonomy's failure clusters with the lightest fix. This spec closes the two clusters it does *not* reach — control-plane conflicts (two network managers fighting over one interface, a masked NetworkManager, a keyfile the daemon silently refuses) and the sharper naming of the terminal auth cluster — and adopts the cross-panel run-time privilege model. It is an expansion of a working doctor, not a rewrite. + +* Problem / Context + +The failure taxonomy sorted ~74 real network failure modes into eight symptom clusters. Read against the live classifier (=~/.dotfiles/net/src/net/classify.py=), the net doctor already reaches six of them: cluster 1 (=rfkill=, =manage-device=, no-hardware), cluster 2 (DHCP-failed), cluster 3 (=tunnel-down=, =vpn-policy=), cluster 5 (=resolved-restart=, DNS-not-resolving, =dns-test=/=dns-override=), and cluster 6 (=portal=, =clock-sync=, =proxy=, and the =upstream-not-local= terminal STOP). The classifier's terminal-first ordering already refuses to loop repairs against a wrong password, a held portal, or a VPN-owned route. That is a lot of the taxonomy, already built. + +Two clusters fall through. + +** The control plane can be broken while the radio looks fine (cluster 7) + +The taxonomy's largest untouched cluster is NetworkManager itself. When =dhcpcd.service= runs beside NM's internal DHCP client, or =systemd-networkd= and NM both claim one link, or =iwd= and =wpa_supplicant= are both active, the interface flaps or never leases — and every existing probe reads a plausible-looking radio with no verdict that names the fight. NM masked (=systemctl start= returns "Unit is masked") reads as "NetworkManager isn't running" today, which points =nm-restart= at a service that cannot start. A =.nmconnection= keyfile that isn't =600= root-owned is silently skipped by the daemon, so a saved network "just won't connect" with no signal the doctor surfaces. These are distinct root causes with distinct fixes, and the doctor currently has one verdict (=nm-restart=) covering the whole control plane. + +** The auth cluster is named too coarsely (cluster 4) + +=classify= detects an auth failure from NM state 120 / GENERAL.REASON and returns =needs-user-action= — correct, and correctly terminal. But the taxonomy shows the auth cluster is not one failure: a pure-WPA3/SAE association failure, a hidden SSID never probed, an enterprise cert mismatch, and a wrong regulatory domain are different faults with different next actions, and some (SAE key-mgmt, =wifi.hidden yes=) are one-line profile fixes rather than "re-enter the password." The doctor collapses them all to one message. + +** The flaky/drops cluster needs signal the one-shot doctor doesn't collect (cluster 8) + +Powersave disconnects, roaming stalls, USB autosuspend, no-reconnect-after-resume, firmware crashloops — these are intermittent, and a single-shot "why am I offline right now" probe cannot see them. Naming them needs event-log correlation the doctor doesn't do. This cluster is real but out of v1; it is named here so the boundary is explicit. + +* Goals and Non-Goals + +** Goals + +- Add a control-plane cluster: a probe that detects a second network/DHCP manager active alongside NetworkManager, a masked/failed NM distinct from a merely-stopped one, and a keyfile-permission fault, each with its own verdict and the lightest fix. +- Sharpen the auth verdict: extract the specific auth cluster cause (SAE, hidden SSID, enterprise cert, regdom) so =needs-user-action= names the real next step, and apply the one-line profile fix where one exists. +- Adopt the cross-panel run-time privilege model (Auto / Privileged / Reboot-tail / Guide, resolved from =sudo -n= + tty + GUI), so control-plane repairs that need root (=systemctl disable dhcpcd=, =chmod= a keyfile, =systemctl unmask=) run under the same Confirm/Arm-default floor the audio doctor defined. + +** Non-Goals + +- Rebuilding the existing ladder. Clusters 1/2/3/5/6 stay exactly as they classify today; this spec only adds where the taxonomy shows a gap. +- The flaky/drops cluster (cluster 8). Naming intermittent faults needs event-log correlation that a one-shot doctor doesn't do. Logged to =todo.org=, not built here. +- Turning the doctor into a NetworkManager profile editor. The auth-cluster fixes are limited to the one-line profile settings that get a stuck association online (SAE key-mgmt, hidden flag); it will not manage certificates, enterprise identities, or credential entry — those stay Guide. +- Silent privileged action. Every Privileged/Reboot-tail control-plane repair defaults to Confirm/Arm, never silent Auto — same stance as the audio spec. + +** Scope tiers + +- *v1:* the control-plane conflict probe and its verdicts (rival-manager, NM-masked, keyfile-perms); sharper auth-cluster reason extraction plus the SAE/hidden one-line fixes; adoption of the run-time privilege model for the new root-needing repairs. +- *Out of scope:* the flaky/drops cluster; certificate/enterprise credential management; any change to the six clusters already classified. +- *vNext:* event-log correlation for cluster 8 (powersave/roam/suspend/autosuspend drop signatures); a DoT/DNSSEC-specific verdict distinguishing "the venue resolver mangles DNSSEC" from the generic DNS-not-resolving; per-profile autoconnect/duplicate-profile hygiene. All logged to =todo.org=. + +* Design + +** For the user + +Nothing changes for the six clusters that already work. What changes is that two failure shapes that today produce a wrong or vague verdict start naming themselves. + +When a second manager is fighting NetworkManager for the link, the wall says so by name — "dhcpcd is running alongside NetworkManager and they're fighting over the interface" — and offers the fix (stop the rival) rather than bouncing a connection that will flap again the moment the other daemon re-grabs it. When NM is masked, the verdict distinguishes "masked — it can't start until unmasked" from "stopped," so FIX unmasks rather than uselessly restarting. When a saved network silently won't load because its keyfile is world-readable, the doctor names the permission fault instead of leaving the user to wonder why a known-good network never activates. + +When association fails on auth, the wall stops saying only "authentication failed" and names which auth: a WPA3-only network the profile isn't set for, a hidden SSID that needs the hidden flag, an enterprise network missing its CA cert. The first two carry a one-press fix; the rest tell the user the specific thing to supply. + +** For the implementer + +*** The control-plane probe + +A new read-only probe tier, beside the existing ones, answering three questions the current ladder never asks: + +1. *Is a rival manager active?* Check whether =dhcpcd.service=, =systemd-networkd.service=, or a standalone =iwd.service= is active while NetworkManager is also active and owns (or wants to own) the link. This is a =systemctl is-active= read plus NM's backend setting — bounded, no hang. A rival that is active is the verdict; the fix is =systemctl disable --now <rival>= (Privileged), never a connection bounce. +2. *Is NM masked or failed, as distinct from stopped?* =systemctl is-enabled NetworkManager= returns =masked=; the unit's =ActiveState=/=Result= distinguishes a crash-loop from a clean stop. A masked NM gets an =unmask= verdict (Privileged), not the existing =nm-restart=. +3. *Does the active profile's keyfile have the wrong permissions?* For the selected connection, stat its =/etc/NetworkManager/system-connections/*.nmconnection=; a non-=600= or non-root-owned file is the silent-skip fault. Fix: =chmod 600= + =chown root= (Privileged). + +The probe runs before the existing "NetworkManager isn't running" rule, because a masked NM and a rival-manager fight are both more specific than "not running" and would otherwise be mis-verdicted by it. + +*** The classifier gains control-plane verdicts + +=classify= adds, in terminal-and-specificity order ahead of the generic =nm-restart= rule: =rival-manager= (needs-user-action → Privileged fix), =nm-masked= (fixable → unmask), =keyfile-perms= (fixable → chmod/chown). Each carries evidence naming the specific rival/unit/file. These are additive; the existing rules below them are untouched. + +*** The auth verdict takes a reason + +=gather_context='s existing =auth_failed_reason= (already extracted from GENERAL.REASON and the journal) grows a small classifier: SAE/PMF, hidden-SSID, enterprise-cert, regdom, or generic-PSK. The =needs-user-action= message is keyed off it. For SAE and hidden-SSID — the two with a deterministic one-line profile fix — the verdict becomes =fixable= with a Privileged/Auto profile-modify action (=key-mgmt sae= + PMF, or =wifi.hidden yes=) rather than terminal. The rest stay =needs-user-action= with a sharpened message. + +*** The privilege model + +The new repairs (=systemctl disable <rival>=, =unmask=, =chmod=/=chown= a keyfile, profile-modify) are the net doctor's first root-needing doctor repairs beyond the ones already in =priv.py=. They adopt the cross-panel run-time resolution the audio spec defined: Privileged remedies run silently where passwordless sudo exists (every archsetup install), prompt on a CLI with a tty, and default to Confirm/Arm — never silent Auto. This is the same standard, not a net-specific one; the shared implementation is the tracked cross-panel task. + +* Alternatives Considered + +** Fold the control-plane faults into the existing =nm-restart= verdict + +- Good, because it is zero new classifier surface. +- Bad, because =nm-restart= is the wrong fix for all three: restarting a masked NM fails, restarting NM does not stop a rival =dhcpcd=, and it does nothing for a bad keyfile. A shared verdict would send the doctor's one fix at three faults it can't fix. +- Rejected. Different root causes with different fixes are different verdicts — the same principle the audio spec used for =pulse-hung= vs =pulse-down=. + +** Make the doctor a full profile editor for the auth cluster + +- Good, because it could fix more auth failures automatically. +- Bad, because credential and certificate entry is a genuine user decision, not a repair — the doctor cannot invent an enterprise CA or a password. Auto-editing profiles beyond the two deterministic one-liners risks writing a wrong setting the user then has to unwind. +- Rejected in favor of fixing only SAE key-mgmt and the hidden flag, and guiding the rest. + +** Build the flaky/drops cluster now with a synthetic re-probe + +- Good, because it would catch powersave/autosuspend "works then dies" cases. +- Bad, because a one-shot doctor invoked when the user is already offline has no drop history to read; catching intermittent faults needs the panel's event log correlated over time, which is a separate probe surface. +- Rejected for v1; logged as vNext. + +* Decisions [0/3] + +** TODO The control-plane probe and its three verdicts +Context: cluster 7 is the taxonomy's largest untouched cluster, and the current single =nm-restart= verdict mis-serves a masked NM, a rival manager, and a bad keyfile. +Decision (proposed): we will add a read-only control-plane probe (rival-manager active-check, NM masked-vs-failed-vs-stopped, active-profile keyfile permissions) and three verdicts ahead of the generic =nm-restart= rule, each with the lightest specific fix. +Consequences: the doctor names the fight instead of bouncing a link that will re-flap; harder — three new verdicts and a probe that reads =systemctl= state plus a stat, and the ordering has to sit ahead of the existing not-running rule without disturbing it. +Owner: Craig. By: before Phase 1 lands. + +** TODO How far the auth-cluster fix goes +Context: the auth cluster is terminal today; some members (SAE, hidden SSID) have deterministic one-line profile fixes, others (enterprise cert, credential) do not. +Decision (proposed): we will extract the specific auth reason and make only SAE-key-mgmt and hidden-flag =fixable=; everything else stays =needs-user-action= with a sharpened, cause-named message. +Consequences: two more auth failures self-heal; harder — the doctor now writes to a connection profile, which is a heavier action than a bounce, and the boundary between "fix" and "guide" inside one cluster has to be defended so it doesn't creep into credential management. +Owner: Craig. By: before Phase 2 lands. + +** TODO Adopt the run-time privilege model as the cross-panel standard +Context: the new control-plane repairs need root; the audio spec already defined the four-class run-time model and made it a cross-panel standard. +Decision (proposed): we will adopt it verbatim — Privileged repairs run where passwordless sudo exists, prompt on a tty, default to Confirm/Arm, never silent Auto — sharing the implementation with the other panels rather than reimplementing it. +Consequences: the net doctor's root repairs are consistent with audio/bt/maint; harder — it couples this spec to the shared privilege-model task, so the ordering across panels has to be settled (which panel lands the shared code). +Owner: Craig. By: before Phase 1 lands. + +* Implementation phases + +Each phase leaves the tree green and independently useful, as the existing net phases did. + +** TODO Phase 0 — the control-plane probe (read-only) +Pure engine, no classifier changes. A probe module that reports rival-manager state, NM masked/failed/stopped, and active-profile keyfile permissions into the diag context. =net diag --json= shows the new signals. Fakes: injected =systemctl is-active/is-enabled= results and a temp system-connections tree. + +** TODO Phase 1 — control-plane verdicts + the privilege model +=classify= gains =rival-manager=, =nm-masked=, =keyfile-perms=, ordered ahead of the generic not-running rule. The run-time privilege resolution lands (shared with the cross-panel task) and the three new fixes register as Privileged/Confirm. =net doctor= names them; =net doctor --fix= applies them under the Confirm floor. + +** TODO Phase 2 — the sharpened auth verdict +The auth-reason classifier; SAE and hidden-SSID become =fixable= profile-modify repairs; the rest get cause-named =needs-user-action= messages. Pairwise over (reason × profile-state). + +** TODO Phase 3 — flip this spec to IMPLEMENTED +And log the vNext items (flaky/drops cluster, DoT/DNSSEC verdict, profile hygiene) to =todo.org=. + +* Acceptance criteria + +- [ ] With =dhcpcd.service= active alongside NetworkManager, the doctor reports =rival-manager= naming dhcpcd, and FIX stops it rather than bouncing the connection. +- [ ] A masked NetworkManager reports =nm-masked= (distinct from stopped), and FIX unmasks it. +- [ ] A non-600 keyfile for the active profile reports =keyfile-perms=, and FIX corrects the permissions. +- [ ] A WPA3-only association failure reports the SAE cause and (with --fix) sets the profile's key-mgmt, rather than saying only "authentication failed." +- [ ] An enterprise-cert auth failure stays =needs-user-action= but names the missing CA cert. +- [ ] Every new root-needing repair defaults to Confirm/Arm and never runs silently as Auto. +- [ ] The six existing clusters classify exactly as they do today (regression). + +* Readiness dimensions + +- *Data model & ownership* — the diag context gains control-plane signals (generated per-probe) and a richer =auth_failed_reason= (generated from GENERAL.REASON + journal, as today). The doctor never writes NM config except the two auth profile-modifies and the keyfile-perms fix, all under the Confirm floor. +- *Errors, empty states & failure* — an unreadable =systemctl=/=stat= yields "unknown," never a false rival/masked/perms verdict (the safe direction). Partial reads degrade to the existing behavior. +- *Security & privacy* — SSIDs and connection names are already redacted by =redact.py=; the keyfile probe reads permissions, not secrets. The auth-reason extraction must not leak the PSK (it reads NM's reason string, not the key). +- *Observability* — the wall names the specific rival/unit/file. =--json= carries the new context. +- *Performance & scale* — three =systemctl= reads and a stat; negligible beside the existing probe cost. +- *Reuse & lost opportunities* — reuses =gather_context='s existing auth-reason extraction, =priv.py=, and the shared cross-panel privilege model rather than a net-local one. =classify= stays the single verdict authority. +- *Architecture fit* — the new probe is additive beside the existing tiers; the classifier additions sit ahead of the generic not-running rule and leave the rest untouched. Weak point: ordering — the new verdicts must precede =nm-restart= or a masked/rival case mis-classifies. +- *Config surface* — none new. N/A. +- *Documentation plan* — module docstrings, as the package does today. The wall is the user documentation. +- *Dev tooling* — =make test= and the net panel smoke cover it; the control-plane probe needs injected =systemctl= state, a fixture shape the package already uses elsewhere. +- *Rollout, compatibility & rollback* — additive; =net doctor= with no new fault behaves as today. The auth profile-modify and keyfile-perms fixes change persisted NM state, so both are Confirm-tier and reversible by the user. +- *External APIs & deps* — =systemctl is-active/is-enabled=, =nmcli=, and =/etc/NetworkManager/system-connections= layout are all already used by the engine; no new packages. The exact rival-manager set (dhcpcd/networkd/iwd) is verified against the live system before Phase 0. + +* Risks, rabbit holes, and drawbacks + +The rival-manager check can false-positive if a rival service is active but not actually contending for the same interface (e.g. =systemd-networkd= managing a container bridge while NM owns wifi). The probe must scope the conflict to the link the doctor is diagnosing, not merely "is networkd running" — otherwise it cries wolf on a legitimate split. This is the main correctness rabbit hole and wants a test with a bridge-only networkd. + +The auth-cluster boundary between "fix" and "guide" is a slope. SAE and the hidden flag are safe because they are deterministic and reversible; the temptation is to add "just one more" auto-fix until the doctor is editing enterprise profiles it shouldn't. The Non-Goal is the guardrail; hold it. + +Coupling to the shared privilege-model task means this spec can't fully land until that model exists somewhere. Sequence it: whichever panel lands the shared code first, the others depend on it. + +* Review and iteration history + +** 2026-07-11 Sat @ 00:08:41 -0500 — Craig Jennings — Author +- What: drafted the net doctor expansion from the network half of the failure taxonomy. v1 adds the control-plane cluster (rival-manager, NM-masked, keyfile-perms) and sharpens the auth verdict; the flaky/drops cluster is staged to vNext. +- Why: the taxonomy showed the net doctor already reaches six of eight clusters, and the two it misses (control plane, auth naming) are where its verdicts are wrong or vague today. +- Artifacts: [[file:../design/2026-07-10-net-bt-failure-taxonomy.org][the net/bt failure taxonomy]]; code read across =~/.dotfiles/net/src/net/= (=classify.py=, =diag.py=, =doctor.py=, =repair.py=, =priv.py=). |
