Booting via BMC virtual CD reads the ~2.8 GB filesystem squashfs
sequentially during the live-boot toram copy; a mid-read drop of the
redirected medium loses the whole copy and fails the boot (v14). Split
the rootfs into self-contained semantic layers so a retry re-reads at
most one ~500-700 MiB layer, not everything. This is a resilience /
reduced-re-read mechanism, not a fix for the virtual-media instability.
NVIDIA variants now ship 7 layers (00-base, 05-firmware, 08-desktop,
10-nvidia-driver, 20-nvidia-platform, 30-nvidia-cuda-libs,
40-nvidia-dcgm-cuda) plus an explicit live/filesystem.module that fixes
their OverlayFS order; amd/nogpu keep a single squashfs.
- lib/squashfs-layers.sh: deterministic classifier (dpkg file ownership
plus explicit rules for build.sh-injected files, never a path
substring), per-layer mksquashfs, 800 MiB hard ceiling, unsquashfs -s
plus strict extraction of every layer, merged-rootfs bootability check.
- build.sh: split the monolith after the full lb build, verify and merge,
write the module file, delete the monolith only then; abort before ISO
assembly on any failure. Runs the builder test suites up front.
- fast-path: force a full build for a multi-layer medium;
fast_path_repack_squashfs hard-refuses (it would drop layers).
- iso-validation.sh: validate_iso_squashfs_layers (module vs layer set
match, size ceiling, no lone giant squashfs) and
validate_iso_media_integrity (xorriso -check_media).
- bee-install: honour filesystem.module order, abort on any layer failure.
- 9013-toram-retry: record the real rsync exit code (it printed a false
rc=0) and correct the "resumes the tail" comment (rsync without
--partial keeps only fully-copied layers). No unsafe partial resume.
- tests: test-squashfs-layers.sh plus a multi-layer guard in
test-build-libs.sh; both run at the top of every build.
- docs: bible-local architecture and decision, iso/README, iso-build-rules.
Verified by a full nvidia build: 7 layers 622/199/256/466/37/567/562 MiB,
every validator passes, xorriso -check_media good, merged rootfs bootable.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
pci=realloc was forcing a full PCI resource reallocation on every default
and toram boot, added as a GPU BAR workaround for BIOS without Above 4G
Decoding. On a dense NVMe-backplane server it exhausted MMIO32 space and
silently dropped 4 of 6 NVMe controllers from the OS even though the BIOS
and lspci both saw them fine. It now only applies to the no-GUI/gsp-off
troubleshooting entry, alongside a bible-local ADR for the two prior
rounds of SAT/blackbox durability work.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Disabled PCIe devices (sysfs enable==0) carry no data traffic; their
link state has no operational impact. Switchtec PCIe switch management
endpoints on NVIDIA HGX H100 baseboards (and similar fabric controllers)
train at reduced speed intentionally and were producing spurious warnings.
Check is vendor-agnostic: reads enable attribute via existing helper,
no vendor/device ID hardcoding.
Documented in bible-local/decisions/2026-06-12-pcie-disabled-device-link-warning.md.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>