Phase 5 of v0.3. Adds an explicit, on-disk state machine to the update agent
so the lifecycle of an attempt is observable end-to-end, instead of being
inferred from logs and side effects.
New package update/pkg/state:
- Phase enum (idle, checking, downloading, staged, activated, verifying,
success, rolled_back, failed)
- UpdateState struct persisted to /var/lib/kubesolo/update/state.json
(overridable via --state). Atomic write (.tmp + rename). Survives reboots
and slot switches because the file lives on the data partition.
- Transition helper that bumps AttemptCount when an attempt starts, resets
it when the target version changes, sets/clears LastError on
failed/success transitions, and stamps StartedAt + UpdatedAt.
- 13 unit tests cover the lifecycle, atomic write, version-change reset,
error recording, idempotent SetFromVersion, garbage-file handling.
Wired into the existing commands:
- apply.go transitions Idle -> Checking -> Downloading -> Staged, with
RecordError on any step failure. Reads the active slot's version file to
populate FromVersion.
- activate.go transitions to Activated.
- healthcheck.go transitions Activated -> Verifying -> Success on pass,
or to Failed on fail. Skips transitions if state isn't post-activation
(manual healthcheck on a stable system shouldn't churn the state).
- rollback.go transitions to RolledBack with LastError="manual rollback".
- check.go intentionally untouched — checks are passive queries, not
attempts; they shouldn't reset AttemptCount.
status.go gains a --json mode that emits the full state report (A/B slots,
boot counter, full UpdateState) for orchestration tooling. Human-readable
mode also prints an Update Lifecycle section when state.phase != idle.
pkg/metrics gains three new series, derived from state.json at scrape time:
- kubesolo_update_phase{phase="..."} — 1 for current, 0 for all others;
all nine phase values always emitted so dashboards see complete series
- kubesolo_update_attempts_total
- kubesolo_update_last_attempt_timestamp_seconds
Server.SetStatePath() configures the file location; defaults to absent
which emits Idle defaults. Three new tests cover the absent / active /
all-phases-emitted cases.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Security hardening: bind kubeconfig server to localhost, mount hardening
(noexec/nosuid/nodev on tmpfs), sysctl network hardening, kernel module
loading lock after boot, SHA256 checksum verification for downloads,
kernel AppArmor + Audit support, complain-mode AppArmor profiles for
containerd and kubelet, and security integration test.
ARM64 Raspberry Pi support: piCore64 base extraction, RPi kernel build
from raspberrypi/linux fork, RPi firmware fetch, SD card image with 4-
partition GPT and tryboot A/B mechanism, BootEnv Go interface abstracting
GRUB vs RPi boot environments, architecture-aware build scripts, QEMU
aarch64 dev VM and boot test.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Implement atomic OS updates via A/B partition scheme with automatic
rollback. GRUB bootloader manages slot selection with a 3-attempt
boot counter that auto-rolls back on repeated health check failures.
GRUB boot config:
- A/B slot selection with boot_counter/boot_success env vars
- Automatic rollback when counter reaches 0 (3 failed boots)
- Debug, emergency shell, and manual slot-switch menu entries
Disk image (refactored):
- 4-partition GPT layout: EFI + System A + System B + Data
- GRUB EFI/BIOS installation with graceful fallbacks
- Both system partitions populated during image creation
Update agent (Go, zero external deps):
- pkg/grubenv: read/write GRUB env vars (grub-editenv + manual fallback)
- pkg/partition: find/mount/write system partitions by label
- pkg/image: HTTP download with SHA256 verification
- pkg/health: post-boot checks (containerd, API server, node Ready)
- 6 CLI commands: check, apply, activate, rollback, healthcheck, status
- 37 unit tests across all 4 packages
Deployment:
- K8s CronJob for automatic update checks (every 6 hours)
- ConfigMap for update server URL
- Health check Job for post-boot verification
Build pipeline:
- build-update-agent.sh compiles static Linux binary (~5.9 MB)
- inject-kubesolo.sh includes update agent in initramfs
- Makefile: build-update-agent, test-update-agent, test-update targets
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
