os.path.isdir() returns False both when a snapshot directory does not exist and
when it cannot be stat'd. Staging aborted either way -- correct -- but reported
every case as "has no snapshot", which sends you hunting for a snapshot that is
sitting right there.
Found while dry-running the planner against a real recursive snapshot of Tap:
running as a non-root user, /mnt/Tap/apps/paperless/data is mode 0700 and the
probe reported "has no snapshot" when `zfs list` showed the snapshot present.
Middleware runs as root so this would not fire in production, but a backup
system must not misreport why it failed.
plan_staging now takes a probe() that classifies the path as ok / missing /
unreadable, and the error names which.
Dry-run results against Tap (250 datasets, real `zfs snapshot -r`):
- 170 mounted filesystems under /mnt/Tap/, and the plan produces exactly 170
descendant mounts -- no omissions
- 18 legacy-mountpoint datasets reported as skipped, never dropped silently
- Tap/ix-apps mounts at /mnt/.ix-apps, correctly outside the backup path
- parent snapshot exposes 0 entries under /apps; the staged sources expose 71,
and lidarr/config resolves with lidarr.db present
- snapshot_tree_names() identifies all 250; deleting only the parent (what stock
does) leaves 249 orphans, and the sweep clears them
Opt-in
------
Nested-dataset snapshot support changes how backups read their source data, so
it is now off by default and gated behind a marker file:
install.sh --enable-nested-snapshots
install.sh --disable-nested-snapshots
With neither flag install.sh preserves the current setting, so a routine
`git pull && bash install.sh` can never silently flip it. When disabled,
apply.sh skips the patch entirely and the stock guard remains. uninstall.sh
tears down staging mounts and removes the marker.
Snapshot lifecycle
------------------
zfs.snapshot.delete defaults to recursive=False and stock restic_backup() calls
it with no options. Stock is safe only because its validation means recursive is
never True in the field. Enabling nested datasets makes recursive snapshots real:
the parent then has one child snapshot per descendant dataset (160+ on an Apps
pool), so stock's delete would orphan every child on EVERY successful run.
The patch now owns the lifecycle end to end:
- delete_snapshot_tree() sweeps the parent and all children, and is idempotent
against stock's finally winning the race once our mounts are released
- on a staging failure the tree is deleted here, because sync.py never completes
`snapshot, local_path = await create_snapshot(...)` and so its finally deletes
nothing at all
- the snapshot is recorded in a sidecar file before anything is mounted, so a
middlewared restart mid-backup cannot orphan it
- a crashed run's snapshot tree is reclaimed on the next run instead of being
overwritten and leaked
Silent-omission fix
-------------------
The dataset list is now enumerated AFTER the snapshot. Read beforehand it could
miss a dataset created in the gap, which the recursive snapshot would capture but
the staging plan would not -- silently omitting its data. Read afterwards, an
unsnapshotted dataset trips the staging check and fails the run loudly.
Also from the audit
-------------------
- plan_staging scopes by dataset name, so skipped-dataset warnings no longer
include every mountpoint-less dataset on the box, which buried the ones that
matter
- staging_root_for rejects "." / ".." components that would escape the staging
base, and resolves STAGING_BASE at call time rather than freezing it into a
default argument
- uninstall.sh no longer `rm -rf`s a tree that may still contain live bind
mounts, and unmounts by path depth rather than string length
- apply_plan takes an injectable isdir; verify_staged drops an unused parameter
- pin the shellcheck action instead of tracking @master
61 tests, ruff and shellcheck clean.
TrueCloud Backup's "Take Snapshot" option is rejected on any path containing
child datasets:
This option is only available for datasets that have no further nesting
That excludes every pool running Apps, where each app is its own dataset and
often has config/pgdata children. Without the option the backup reads live
files, so databases are captured mid-write and an app that continuously
rewrites its files can stall a run as restic chases a moving target.
The stock guard is correct and must not simply be removed. create_snapshot()
already takes a recursive ZFS snapshot, but points the backup tool at the
parent dataset's .zfs/snapshot/, and ZFS does not expose child datasets there:
/mnt/Tap/.zfs/snapshot/<snap>/apps/ -> 0 entries
/mnt/Tap/apps/lidarr/config/.zfs/snapshot/<snap>/ -> the real data
Deleting the check would make restic walk a near-empty tree, report success,
and upload almost nothing.
Implement the missing traversal instead. After the recursive snapshot is taken,
each descendant dataset's own .zfs/snapshot/<snap> is bind-mounted into a
staging tree mirroring the original layout, and the backup tool is pointed at
the staging root. The guard is relaxed only after that machinery is in place.
Safety properties:
- staging failure aborts the backup; a partial tree is never handed to restic
- a post-mount pass asserts every target is a mountpoint and the root is
non-empty, so this cannot regress into the empty backup it exists to prevent
- apply.sh patches crud.py last, so a partial failure leaves the guard intact
rather than exposing "guard removed, traversal missing"
- every injected block no-ops when _truecloud_nested is absent
- unmountable/locked datasets are skipped and reported, never dropped silently
- scoped to cloud_backup; cloudsync has no teardown wired in, so its guard stays
The staging root is stable per task, so restic can find its parent snapshot
between runs; stock's timestamped .zfs path changes every run and forces a
full re-scan.
Add CI (shellcheck, bash -n, ruff, pytest on 3.11-3.13), including tests that
compile the *_BLOCK strings, which are Python source appended to live
middlewared modules and were previously unchecked.
Also: sync stale version strings, untrack a committed .pyc, gitignore
__pycache__.
The tool created cloud_backup tasks via POST /api/v2.0/cloud_backup, which is deprecated
and removed in TrueNAS 26.04. It now calls the middleware directly with midclt
(cloudsync.credentials.query / cloud_backup.query / cloud_backup.create), so it runs on
the TrueNAS host with no host address or API key. --host/--api-key/--insecure are kept
accepted-but-ignored for compatibility. Dropped the ssl/urllib HTTP client. v0.2.0.
flan