Start with freshness
An ONLINE pool is the last reported state, not proof the server is currently reachable. Check collection time and partial/stale indicators before acting.
Follow the topology
Pool tabs preserve pool → vdev → device hierarchy, including replacement groups and data, log, cache, special, dedup and spare roles. Expand a device for identity, SMART and physical location. Unmatched devices remain visible without guessed identities.
Keep accounting separate
Pool physical allocation and dataset accounting answer different questions. Parent and child capacity rows overlap: do not add them together. Root datasets, child filesystems and zvols expose used, available, referenced, compression and mountpoint information.
Inspect native status
Read the retained verbose pool status for action advice, scan progress and permanent-error paths. Missing values remain unknown; a failed collection retains earlier data with a stale label.
Source reference
Read the upstream documentation ↗Reviewed against main on November 1, 2026. Interface labels and capabilities can change.