resilver · shipping · also ZFS resilver, Resilvering

Resilver

A resilver is ZFS's process of bringing a newly attached, replacement or out-of-date device into agreement with the data it must hold.

Related Observatory article: Resilver on hesela.com

A resilver targets data requiring synchronization; a normal full scrub checks stored data for otherwise unnoticed checksum errors [1]. In OpenZFS 2.3, replacement with -s uses sequential reconstruction and starts a scrub afterward because that reconstruction does not verify checksums; this replacement mode does not support RAID-Z [2].

Relations

related

raid-rebuild, data-scrubbing, degraded-array, hot-spare, checksum, mirroring

Limitations

• Attaching a mirror member does not immediately add its full redundancy: the resilver must complete. [3]

Citations

1. OpenZFS 2.3: zpool-scrub(8), scrub versus resilver (accessed 2026-10-13)
2. OpenZFS 2.3: zpool-replace(8), replacement and sequential reconstruction (accessed 2026-10-13)
3. OpenZFS 2.3: zpool-attach(8), when a mirror gains redundancy (accessed 2026-10-13)
4. Hesela: RAID rebuild read-error models and resilver boundaries (accessed 2026-10-13)

JSON: /data/terms/resilver.json