With ZFS, we can enable copies=[1,2,3] to configure how many copies of data there are. With copies of 2 or more, in theory, an entire disk can have read errors, and the zfs volume still works.
The unfortunate part here is that the redundancy lies in the volume, not the pool vdev like with raidz or mirroring. So if a disk were to go missing, the zpool (stripe) is missing a vdev and thus becomes offline. If a single disk in a raidz vdev is missing, it would become degraded and still usable. Now, with non-redundant stripes, the disk can't be replaced, but all the data is still there with copies=2 if a disk dies. Is there not a way to force the zpool online or prevent it from offlining itself? One of the key benefits of the metadata copies is that if a single block fails, the filesystem is still navigable to grab what data is possible. -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
