Re: raid1 issue after disk failure: both disks of the array are still active

On Sep 13, 2012, at 4:34 AM, Robin Hill wrote:

Your best bet now is to do an array check:
   echo check > /sys/block/md0/md/sync_action

This will force a read of all disks in the array. This should trigger
the read error, causing an attempt to re-write the faulty block, in turn
causing the drive remap the bad sector (assuming the re-write fails).

"check" records errors, no action is taken by the md driver to correct it, although the disk firmware itself may try reallocation. So far, that appears to not be the case. 

"repair" causes the md driver to write correct data (from copy or reconstructed from parity), which should force the disk firmware to reallocate the affected LBAs from bad physical sectors to good ones.

It seems in this case "repair" is indicated.


Chris Murphy