The safety review of the first version found it safe for the pool's data and asked for these fixes before
it goes on the home server:
- zfs_snapshot: no recursive. Every answer gives the dataset's free space and the pool's capacity, and
says that the snapshot holds every block deleted or overwritten until it is destroyed by hand.
- A command that runs out of time is ended with its whole process group. An act that timed out is
answered from the list, or as "outcome unknown", never as "NOT DONE".
- The watch runs as the operator account.
- The event follower reads ZFS's queue from its start, with a cursor per boot, so the pool's import and
any downtime reach the journal once. It writes "dropped N events", kills zpool before waiting for it,
and exits non-zero after five failed follows in a row.
- Past error counts are a warning, and counts that rise are unhealthy.
- The guard test catches .Run(, exec.Command(, exec.CommandContext( and process starts.
- The fixtures and the parser follow OpenZFS 2.4.4's own printers: human scan sizes under -p, no iostat
section lines, error scrubs, per-vdev rebuild resilvers, paused scrubs.
The operator also asked the module to own the scrub. A timer and a service of the module's own run
zpool scrub -w -- <pool> from the scrub-pool, scrub-cadence, scrub-day and scrub-time settings. In the
same declaration, the distribution's weekly and monthly timers for that pool are held stopped and
disabled, so exactly one schedule scrubs it. zfs_scrub shows the schedule and the next run, with any
resilver's progress. zfs_scrub_start, zfs_scrub_pause and zfs_scrub_stop act with why. The health check
warns of a late or failed scrub and of a running resilver, and is unhealthy for a resilver that finished
with errors.
jochen
e69506a26f