Erich Blume
66a47738dd
Update manage-lockfile doc with post-deploy steps (kernel update detection, reboot guidance, generation pruning). Add prune-ringtail-generations mise task that keeps the 5 most recent generations plus the most recent one matching the booted kernel for safe rollback. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2.6 KiB
| title | modified | tags | |||
|---|---|---|---|---|---|
| Manage Ringtail Lockfile | 2026-03-27 |
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Manage Ringtail Lockfile
Two dagger pipelines manage the ringtail NixOS flake lockfile (nixos/ringtail/flake.lock) for different purposes.
Update All Inputs
To pull the latest versions of all flake inputs (equivalent to nix flake update):
# 1. Update flake.lock
dagger call flake-update --src=. --flake-path=nixos/ringtail \
export --path=nixos/ringtail/flake.lock
# 2. Commit, push, then deploy
git add nixos/ringtail/flake.lock
git commit -m "Update ringtail flake inputs"
git push
mise run provision-ringtail
After deploying, continue with post-deploy maintenance.
Lock New Inputs Only
mise run provision-ringtail automatically runs flake-lock before deploying. This resolves any newly added inputs without upgrading existing ones (equivalent to nix flake lock). If the lockfile changes, the task stages the file and exits — commit, push, and re-run.
This is the right behavior for provisioning: configuration changes that add a new input get locked, but existing inputs stay pinned until explicitly updated.
Post-Deploy Maintenance
After provision-ringtail completes (whether from a full update or a config change), perform these steps.
Check for Kernel Update
Compare the booted kernel against the one in the current system profile:
ssh ringtail 'echo "Booted: $(uname -r)"; echo "Staged: $(readlink /run/current-system/kernel | grep -oP "linux-\K[^/]+")"'
If they differ, a reboot is needed for the new kernel to take effect. Reboot at a convenient time:
ssh ringtail 'sudo reboot'
AI agents: Do not reboot automatically. Inform the user that a kernel update is pending and suggest they reboot when convenient.
Prune Old Generations and Garbage Collect
Old NixOS system generations accumulate over time. The prune-ringtail-generations task handles pruning and garbage collection together:
mise run prune-ringtail-generations # keep 5 most recent + kernel-safe gen
mise run prune-ringtail-generations --dry-run # preview only
mise run prune-ringtail-generations --keep 3 # keep fewer generations
The task keeps the 5 most recent generations plus the most recent generation whose kernel matches the currently booted kernel — this preserves a rollback target that won't require a reboot. After pruning, it runs nix-collect-garbage to free unreferenced store paths.