Commit Graph
5 Commits
Author SHA1 Message Date
jakman85andClaude Opus 5 a78f010368 feat(node-health): probe the Intel render device, read-only
gate / gate (pull_request) Successful in 1m40s
gate / conformance (pull_request) Has been skipped
The prod nodes already have a working Intel render device — measured by hand on
all three on 2026-09-30. Nothing here installs, loads or changes anything; the
point is that the measurement now re-runs on every health run instead of decaying
silently in a handoff note.

The failure being hunted is silent by construction: Plex hardware-transcodes
through /dev/dri/renderD128, and if that node stops existing (node rebuild, a BIOS
change that disables the onboard IGD, a kernel that binds a different DRM driver)
Plex falls back to software transcoding on its own and the only symptom is a hot
CPU.

All of it is in the UNPRIVILEGED collector pass: lstat() on /dev/dri/*,
grp.getgrgid() for the owning group name, the /sys/class/drm/card*/device/driver
symlink for the bound driver, /sys/bus/pci/devices/*/class for display-class
devices whether or not a driver is bound, /sys/class/drm/card*/engine/* for the
vcs*/vecs* media engines, /proc/modules and /proc/cmdline. lspci and vainfo are
probed but never depended on — neither is in node_baseline's package floor.

Three checks, in the role's existing PASS/WARN/FAIL/SKIP/INFO shape:

  graphics.render_device  the outcome — a usable character-special renderD* node.
                          FAIL only when a display device IS on the PCI bus and
                          there is still no render node. SKIP when the machine has
                          no display device at all (a VM guest), which is why the
                          PCI scan is separate from the DRM scan: /sys/class/drm/
                          card* exists only once a driver has BOUND.
  graphics.drm_driver     what is bound, against the new
                          node_health_graphics_expected_driver default (i915), so
                          the comparison is data and not task logic. `xe` bound in
                          place of i915 is a WARN, not a FAIL: the device works but
                          the userspace media stack differs.
  graphics.media_stack    INFO only, deliberately. GuC/HuC off (i915.enable_guc=0)
                          is an accepted state that costs low-power H.264 encode
                          quality only, and no host vainfo is not a defect at all
                          because Plex ships its own libva inside its container.

The render node's owning group and GID are REPORTED, never asserted: `render` is a
systemd dynamic allocation rather than a Debian static gid, so a rebuild can
legitimately move it off the 992 measured today, and Plex's container entrypoint
stats the device and joins whichever group owns it. Drift stays visible without
being an error.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
2026-09-30 13:04:43 -05:00
jakman85andClaude Opus 5 cf33338448 feat(node_health): detect the EFI memattr bug on every run, two independent ways
The fault is BOOT-TO-BOOT NON-DETERMINISTIC — the same machine booted correctly two boots
earlier — so it has to be detected on every health run, not diagnosed once. And node 1 is
exposed to the identical lottery on every reboot while currently looking healthy.

firmware.efi_memattr — reads the kernel ring buffer and distinguishes six states:
  Failed to map EFI Memory Attributes table @ 0x..   -> FAIL (memory lost NOW)
  Unexpected EFI Memory Attributes table version <N> -> WARN (corrupt table still published;
                                                        intact only by luck)
  [Firmware Bug]: Corrupted EFI ... detected!        -> PASS (the >=6.13 fix working)
  no memattr line, log reaches early boot            -> PASS (no table / accepted / not UEFI)
  no memattr line, log does NOT reach early boot     -> SKIP
  dmesg unreadable                                   -> SKIP

memory.physical_total — deliberately a SEPARATE check, not folded in: it measures the SYMPTOM
with no kernel log at all, so an unreadable-dmesg node is still not unmeasured. Two sub-verdicts,
worst wins: /proc/zoneinfo present-vs-managed (world-readable, works on metal and VMs — sum of
managed IS MemTotal) and MemTotal vs the DIMM total from dmidecode. Thresholds 10% WARN / 25%
FAIL, set from measured baselines: 2.0% prod-1, 2.1% workstation, 2.2% dev VM, vs 83.4% prod-2.

THREE GUARDS AGAINST A FALSE PASS, because "no memattr line" must never silently mean "fine":
1. dmesg failure yields available:false with the exact reason (rc, uid, kernel.dmesg_restrict) -> SKIP
2. the ring buffer WRAPS and every memattr line prints in the first fraction of a second, so the
   collector records a boot_covered anchor (Linux version / BIOS-provided physical RAM map); no
   memattr line WITHOUT that anchor is a SKIP, not a PASS
3. memory.physical_total needs no kernel log at all
Verified by forcing the unprivileged path: SKIP with the EPERM reason while zoneinfo still PASSed.

VERDICTS, confirmed live:
  k3s-prod-1  WARN "EXPOSED, not immune ... survived only because its garbage version field read
                    1030, which is > 2 ... one unlucky boot from the failure state" + PASS 2.0%
  k3s-prod-2  FAIL "THIS NODE HAS LOST MEMORY TO THE BUG ... at 0xbeeb0018" + FAIL 83.4%/83.6%
  k3s-dev-*   PASS both, NO false finding: "no UEFI config-table line ... did not boot via UEFI.
                    Log reaches back to early boot, so that absence is measured, not assumed."
Both failure texts carry the remediation verbatim, including that there is NO kernel cmdline
workaround because efi_memattr_init() runs before any efi= bail-out.

Root-gating follows the role's existing pattern: --privileged re-runs THE SAME collector under
become, only when the unprivileged pass actually failed to read something. Reimplementing the log
grep and SMBIOS parse in Jinja would have been a second source of truth for the same fact.

LATENT BUG FIXED in passing: the collector's run() used bare shutil.which(), so dmidecode (in
/usr/sbin) was invisible under the unprivileged k3s PATH and produced a FALSE "not installed"
skip reason. Now shares the sbin-aware which() collect_tools() already had.

INCIDENTAL FINDING recorded in §0b: node 1's DIMMs are NOT a matched pair — DIMM1 Micron
8ATF2G64HZ-3G2E1 (DDR4-3200), DIMM3 Micron 16ATF2G64HZ-2G6E1 (DDR4-2667). Both 16 GB so capacity
is right, but different rank organisation and rated speed, so the pair runs at 2667. Not a fault;
recorded because §2 requires the three nodes to end up symmetric and "2×16 GB Micron" hid it.

Serves: R-ENV-01, R-ENV-03, R-OBS-04. Task: T-7.1.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
2026-09-01 22:30:45 -05:00
jakman85andClaude Opus 5 0b3db6e778 fix(node_health): SMART verdict was wrong by 4096x — judge on portable signals
The first real SMART run FAILED k3s-prod-1's drive on reallocated=61440. That verdict
was WRONG, and the failure mode is instructive: the check trusted a VENDOR-DEFINED raw
value as if it were an ATA-standard sector count.

Micron TN-FD-20 ("SMART Attributes for the C400 SSD") names attribute 5 "Reallocated
BLOCK Count" and defines its raw as grown-bad-blocks x Block_Sector_Count, where
Block_Sector_Count is 256 x 16 = 4096 for the 128Gb-NAND parts (256GB/512GB). This is
the 512GB C400-MTFDDAC512MAM: 61440 / 4096 = 15. Triply corroborated on the drive itself
— attr 170 Grown_Failing_Block_Ct = 15, attr 196 Reallocated_Event_Count = 15, attr 5
normalised value 100 against thresh 10, and `when_failed` empty on every attribute.
FIFTEEN grown bad blocks, not sixty-one thousand bad sectors.

smartctl(8) states it outright: since ATA/ATAPI-4 rev 4 the meaning of raw Attribute
fields is "entirely vendor-specific". So a raw value can never be a portable verdict.

FAIL now comes only from signals that mean the same thing on every drive: the drive's own
smart_status.passed; NORMALISED value vs the MANUFACTURER's own threshold via smartctl's
when_failed ("now"/"past"/""), split Pre-fail -> FAIL and Old_age-or-past -> WARN; the
ATA-standard counters 197/198/187 (199 CRC is WARN-only — it is link, not media); and for
NVMe critical_warning / media_errors / percentage_used. Wear reads from the NORMALISED
lifetime indicator (202/231/233, or NVMe percentage_used) — a percentage by definition.

Vendor raw counts are still collected and PRINTED WITH THEIR NUMBERS, and may raise a
WARN, but can never drive a FAIL. Attribute 5's raw is now shown beside the normalised
reading that contradicts it, labelled vendor-encoded, with a mechanically-derived
"(= 15 x 4096)". Endurance attributes are matched by THE NAME smartctl's drivedb resolved
for that model, not by bare ID — drivedb is the portability layer; on an unrecognised
drive the name is Unknown_Attribute, nothing matches, and the field stays null with no
claim made. The STORAGE section now prints 170/172/173/174/189/206, whose previous
omission is exactly what let the misread stand unchallenged.

Also documented from TN-FD-20: on this family attr 197 "will always be 0, as reallocation
will be done on-the-fly" — so pending=0 is NOT evidence of health here. The role reports
the number and infers nothing from it.

Branches real hardware cannot exercise were verified with a harness rendering the actual
role expressions against synthetic smartctl payloads: virtio/no-stdout -> SKIP; NVMe
healthy -> PASS; NVMe degraded -> FAIL; a genuinely dying ATA drive (attr 5 normalised 8
<= thresh 10, pending 48) -> FAIL driven by the threshold trip and standard counters, not
the raw; unknown-vendor attrs -> PASS with the unnamed counter ignored; failed-in-the-past
-> WARN.

NEW VERDICTS. k3s-prod-1: 0 FAIL / 4 WARN / 12 PASS / 1 SKIP — SMART is a WARN naming the
real findings (31% of rated life consumed, 15 grown bad blocks, 187 erase failures, 32
unexpected power losses on a drive with no power-loss protection). k3s-dev-1: unchanged,
all three virtio disks still SKIP with their stated reason.

BREAKING (JSON artifact): the fact `reallocated_sectors` is renamed and gone — that name
asserted a unit ATA does not guarantee. Replaced by realloc_attr (the whole attribute,
normalised + raw), realloc_events, and grown_bad_blocks. Nothing in the repo reads it.

Serves: R-ENV-03, R-OBS-04.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
2026-09-01 00:40:29 -05:00
jakman85andClaude Opus 5 c1f24e4a6d fix(dns): resilient node resolvers — mechanism-detecting, per-environment (R-DNS-01/03)
Re-authors the fix stranded on origin/fix/node-dns-resilient-upstream (7a34590). That
commit was NOT landed: it wrote a netplan drop-in and ran `netplan apply`, but netplan
does not exist on these nodes any more (Debian 13 trixie generic cloud image; not in
node_baseline_packages). Landing it would have failed the handler with command-not-found
and BROKEN node-baseline.yml on every node — worse than not landing it. Its dev-LAN
literals also sat in role defaults, which prod inherits, pointing prod nodes at a PiHole
on a network they cannot reach.

The underlying problem is real and verified: a SINGLE upstream resolver is a hard SPOF.
PiHole answers jackson.lan instantly but its external recursion flaps — 0/25 for public
names (registry-1.docker.io, quay.io, ghcr.io) while gitea.jackson.lan resolved 5/5 —
breaking containerd image pulls and CoreDNS `forward . /etc/resolv.conf`.

MECHANISM DETECTION (new `dns` tag in node_baseline). Five read-only probes feed one
set_fact yielding three outcomes, because the two environments no longer share a resolver
stack (dev-1 is behind resolved's 127.0.0.53 stub; prod-1 has a direct resolv.conf and no
cloud-init at all):
  * systemd-resolved — resolved running AND owning /etc/resolv.conf (proven by the
    symlink pointing into /run/systemd/resolve/, or by every nameserver being a resolved
    loopback). Writes resolved.conf.d/99-k3s-dns.conf with an ordered DNS=, Domains=, and
    FallbackDNS= EXPLICITLY EMPTIED so systemd's compiled-in public resolvers can never
    silently bypass the local zone and ad-blocking.
  * resolv-conf-file — plain directly-managed file (prod's shape). Ordered nameserver
    lines + options timeout:2 attempts:2, backup: true. Deliberately NO `rotate`, which
    would destroy PiHole-first ordering.
  * contended — resolvconf/openresolv present or NetworkManager active. Writes NOTHING
    and fails loudly: a change that silently gets reverted is worse than no change.
Resolved-running-but-not-owning-resolv.conf correctly falls through to the file branch.
Ordering is the policy that keeps the local zone working — the second server is only
consulted after the first fails, so a gateway NXDOMAIN can never beat PiHole to a
jackson.lan answer.

SEAMS. Dev values in role defaults ([192.168.1.18, 192.168.1.1], search jackson.lan);
prod values in inventory/group_vars/k3s_prod/vars.yml. NOT cluster-vars — that ConfigMap
is consumed by Flux postBuild for platform/ and apps/, and no Ansible code reads it.

PROD'S SECOND UPSTREAM IS AN OPEN OPERATOR DECISION and is left as a loud
BLOCKED-pending-second-upstream placeholder, the same precedent as the node_baseline disk
devices, with a dns-tagged assert that stops the play before any file is written. A
public resolver was NOT invented as a default: it would bypass the local zone, which is a
decision, not a default. PROD-PROVISIONING.md §4 was rewritten (the old bullet pointed at
the now-dropped branch) to state the choice, including that prod routing to the dev
PiHole is unverified across the pfSense boundary.

tofu: servers = [var.dns_server, var.network_gateway] — the one hunk of the old branch
worth taking as-is. Dev-only by nature.

ALSO FIXES A FALSE WARN THIS WOULD OTHERWISE CREATE: node_health_collect.py parsed
/etc/resolv.conf only, so on dev it read the 127.0.0.53 stub and would report a permanent
single-upstream WARN even after a correct fix. It now asks resolvectl for the real
upstreams when it sees the stub — and if that fails, nameservers is NULL with the reason
recorded, never the stub and never a guess. assess.yml turns null into SKIP, not WARN and
not PASS. The honesty discipline is preserved exactly.

Verified with NO play run against any node: syntax-check + yamllint + tofu fmt clean;
--tags packages still selects ONLY the apt task (the prod package-floor escape hatch
bypasses DNS entirely); --list-hosts unchanged; -c local simulation driving the REAL
detection expression and REAL file bodies extracted from the role by script (so the test
cannot drift) passes all 5 scenarios — dev stub -> systemd-resolved, prod shape ->
resolv-conf-file, NetworkManager and resolvconf -> contended; dev defaults pass the
assert byte-identically while prod overrides fail it by name; collector unit-tested
against 8 resolver shapes.

Serves: R-DNS-01, R-DNS-03, R-ENV-02, R-ENV-03.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
2026-09-01 00:11:49 -05:00
jakman85andClaude Opus 5 9f59c36000 feat(ansible): node_health role — read-only hardware health for prod + dev nodes
Operator ask: implement the roles needed to check prod node hardware health, and run
them to find out our state. This is that role; the run's findings are below.

roles/node_health is a read-only sibling to cluster_verify (cluster health vs hardware
health), styled after node_baseline. One unprivileged collector script does the work in
a single SSH round trip — reading /sys/class/dmi, thermal + hwmon, EDAC, cpufreq +
thermal_throttle, /proc/pressure, /sys/block incl. SCSI ioerr/iotmo counters, lsblk,
lscpu, mounts + statvfs, per-NIC stats, resolv.conf.

THE DESIGN POINT: an unreadable field is emitted as null WITH A RECORDED REASON, never
as zero. The summary ends with a "NOT READ (and why) — these are UNKNOWNS, not passes"
section. A fake zero on a reallocated-sector count is exactly the kind of false green
this project refuses. 22 checks report PASS/WARN/FAIL/SKIP/INFO; every SKIP says why.
Report-only by default; thresholds live in defaults/main.yml.

Portable across bare metal AND VMs — validated against k3s-prod-1 (bare metal, no root)
and k3s-dev-1 (VM, root). VM-absent things (SMART on virtio, coretemp, EDAC) skip
cleanly, and iSCSI/Longhorn volumes are split out of the physical-disk set so a live
replica is never mistaken for a spare device.

playbooks/node-health.yml takes its target group as a variable (-e node_health_hosts=
k3s_prod), deliberately unlike the other playbooks that hardcode k3s_servers — see the
group-name gap already flagged in hosts.ini.

Two become facts found the hard way and documented in the role: a group_vars
`ansible_become: true` OUTRANKS `become: false` as a play/task keyword, so unprivileged
tasks must override the variable; and `failed_when: false` does NOT catch "Missing sudo
password" — only `ignore_errors` does.

FIRST RUN, k3s-prod-1, 2026-08-31: 0 FAIL · 3 WARN · 12 PASS · 3 SKIP · 4 INFO.
Box is healthy, cool and unstressed: i7-9700T 8C/8T, VT-x + /dev/kvm (KubeVirt OK), zero
throttle events, hottest sensor 33C, PSI 0.00 across the board, 31.1 GiB RAM, eno1 up at
1000 Mb/s, BIOS R21 02.26.00, no reboot pending.

DRIVE HEALTH IS STILL UNKNOWN — the headline. SMART did not run, blocked TWICE over: no
vaulted ansible_become_password for prod, AND smartmontools is not on the node at all
(node_baseline has never run there). Power-on hours, wear, reallocated/pending sectors
and drive temperature all remain unmeasured on a ~2011 consumer SSD.

WARNs: kernel ioerr_cnt=6 on sda (read cautiously — four freshly attached iSCSI disks on
dev each showed a flat 7, suggesting a fixed per-device discovery cost, not media
trouble; attribution needs dmesg/root); 0.95 GiB swap still active (node_baseline does
the swapoff); one IPv4 resolver only (the other two upstreams are IPv6 Google), which
refines rather than resolves the DNS-SPOF finding.

ESCALATION — ECC status is UNKNOWABLE on this hardware: /sys/devices/system/edac/mc
exists but no controller is bound. Non-ECC consumer RAM. Silent memory corruption on a
prod node would be undetectable. Recorded as a SKIP with reason, not a pass.

Serves: R-ENV-01, R-ENV-03, R-OBS-04. Task: T-7.1.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
2026-08-31 23:20:25 -05:00