Re: [Bug-ddrescue] (Not-a-bug) just question about 520-bytes-perfectly drives

[Antonio Diaz Diaz]

Hello Oleg,

Oleg Krutov wrote:
> Is it physically possible to read data from SAS/SCSI drives that have more
> than 512 (usually -- 520) bytes per sector? These drives are not properly
> detected by kernel ("Unsupported sector size 520. 0 512-byte logical
> blocks"), so it can be read only via sg_raw utility by direct scsi
> commands, by little chunks and very slowly. Maybe there is an opportunity
> to read a drive "more directly" than with O_DIRECT flag?

Mi intention has been always to keep ddrescue simple, so I do not plan 
to implement complicated workarounds to access drives not supported by 
the kernel. IMHO hardware access belongs in the kernel. Maybe ddrescue 
can be compiled on a system whose kernel (not linux) supports 520-byte 
sectors?


Scott Dwyer wrote:
> But did everyone forget my older passthrough patches for ddrescue?
> They are still available in the downloads section for ddrutiltiy on
> sourceforge. A smart person could possibly hack the patch and
> potentially make a version of ddrescue that could read those drives.
> Not an easy task, but possible.

I have not forgotten your patch, but I am reluctant to spend time 
implementing non-standard things, given the amount of more useful things 
I have to do. :-)


Best regards,
Antonio.