You are asking for a low level cache (editable cache), and it could be much interesting for sector 0 problems and other situations.
I don't know if deploying a RAID1 simulation could make Linux to read bad sectors from mirror device. On 07/02/16 04:15, Paul Daniels wrote: > Sorry, I should have been more specific about the particular situation > that arises. > > When sector-0/partition-table is physically damaged and non-recoverable > it sometimes causes the drive to "offline" itself when you try to read > it, as such you can never recover these drives with ddrescue+linux > because linux will attempt to read that partition table each time you > power the drive up. > > What would be nice is if there was an overlay facility/magic in linux > where, if you already had a copy of the data in that area (or even just > fake), you could make linux read the partition/data from the image/clone > and switch to the real drive for other areas. > > Hope that clears matters up. > > > On 07/02/16 03:09, Narcis Garcia wrote: >> Partition table and drive presence are 2 unrelated things. >> Partition table is data, and drive is a device. >> Sector 0 should be copiable without any MBR/GPT/etc data in it. >> >> >> On 06/02/16 14:08, Cameron Andrews wrote: >>> That doesn't work though if Linux says "nope, there is no drive here" >>> when it cannot find the partition table.. ie: the /dev/sdX is not >>> present for the drive because no table was readable... >>> >>> On 06/02/16 03:31, Antonio Diaz Diaz wrote: >>>> Narcis Garcia wrote: >>>>> Number of disk sectors could be specified to ddrescue? >>>> Sure: >>>> ddrescue --size=123456s >>>> >>>> _______________________________________________ >>>> Bug-ddrescue mailing list >>>> Bug-ddrescue@gnu.org >>>> https://lists.gnu.org/mailman/listinfo/bug-ddrescue >>> >>> _______________________________________________ >>> Bug-ddrescue mailing list >>> Bug-ddrescue@gnu.org >>> https://lists.gnu.org/mailman/listinfo/bug-ddrescue >> _______________________________________________ >> Bug-ddrescue mailing list >> Bug-ddrescue@gnu.org >> https://lists.gnu.org/mailman/listinfo/bug-ddrescue >> > _______________________________________________ Bug-ddrescue mailing list Bug-ddrescue@gnu.org https://lists.gnu.org/mailman/listinfo/bug-ddrescue