ZFS i/o errors - which disk is the problem?

[Tz-Huan Huang]

2008/1/7, Bernd Walter <ticso at cicely12.cicely.de>:
> The data is corrupted by controller and/or disk subsystem.
> You have no other data sources for the broken data, so it is lost.
> The only garantied way is to get it back from backup.
> Maybe older snapshots/clones are still readable - I don't know.
> Nevertheless data is corrupted and that's the purpose for alternative
> data sources such as raidz/mirror and at last backup.
> You shouldn't have ignored those errors at first, because you are
> running with faulty hardware.
> Without ZFS checksumming the system would just process the broken
> data with unpredictable results.
> If all those errors are fresh then you likely used a broken RAID
> controller below ZFS, which silently corrupted syncronity and then
> blow when disk state changed.
> Unfortunately many RAID controllers are broken and therefor useless.

Hi,

Thank you very much for your answer.

We have run the self-test for all raid controllers and they all reported ok.
Do you mean that many raid controllers are broken (buggy?) even if the
self-test is passed? If all the disks are pass-through to the zfs, is
it the safe
way to use the buggy controllers?
Thank you very much.

Sincerely yours,
Tz-Huan