On Jul 28, 2010, at 12:41 PM, sol wrote: > Having just done a scrub of a mirror I've lost a file and I'm curious how this > can happen in a mirror. Doesn't it require the almost impossible scenario > of exactly the same sector being trashed on both disks? However the > zpool status shows checksum errors not I/O errors and I'm not sure what > that means in this case.
It means that the data read back from the disk is not what ZFS thought it wrote. > I thought that a zfs mirror would be the "ultimate" in protection but it's > not! Are you saying you would rather have the data silently corrupted? > Any ideas why and how to protect against this in the future? This can happen if there is a failure in a common system component during the write (eg. main memory, HBA, PCI bus, CPU, bridges, etc.) > (BTW it's osol official release 2009.06 snv_111b) On more modern releases, the details of the corruption are shown in the FMA dump. However, this feature does not exist in OpenSolaris 2009.06. -- richard > > # zpool status -v > pool: liver > state: ONLINE > status: One or more devices has experienced an error resulting in > data corruption. Applications may be affected. > action: Restore the file in question if possible. Otherwise restore the > entire > pool from backup. > see: http://www.sun.com/msg/ZFS-8000-8A > scrub: scrub completed after 3h31m with 1 errors > config: > > NAME STATE READ WRITE CKSUM > liver ONLINE 0 0 1 > mirror ONLINE 0 0 2 > c9d0p0 ONLINE 0 0 2 > c10d0p0 ONLINE 0 0 2 > > errors: Permanent errors have been detected in the following files: -- Richard Elling rich...@nexenta.com +1-760-896-4422 Enterprise class storage for everyone www.nexenta.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
