ZFS and DMA read error

[Mark Stapper]

Arthur Chance wrote:
> Mark Stapper wrote:
> [snip]
>> I ordered a "spare" drive so I'll wait until it arrives, replace the
>> faulty drive with this one by dd-ing data from one to the other (I have
>> only 4 SATA ports so I can't do "zpool replace").
>
> zpool replace has two forms
>
>     zpool replace pool old-device new-device
>
> and
>
>     zpool replace pool device
>
> The latter is for when you pull the old drive and put the new one on 
> the same {S,P}ATA port because you've no free ports. I did that a 
> couple of weeks ago when one of my raidz drives fried (in its warranty 
> period!) and it worked like a dream. I did a zpool replace and then a 
> zpool scrub  to make sure everything was OK because of this section of 
> the zpool man page:
>
>     Scrubbing  and resilvering are very similar operations. The differ-
>     ence is that resilvering only examines data that ZFS  knows  to  be
>     out  of  date (for example, when attaching a new device to a mirror
>     or replacing an existing device), whereas  scrubbing  examines  all
>     data to discover silent errors due to hardware faults or disk fail-
>     ure.
>
Thanks for the tip. I'll be sure to try that.