Talk:ND-210628F

Data recovery attempts

I have previously used dd_rescue successfully, but only on hard drives. My experience with data recovery from floppies is limited, and I worry about potential wear on the floppies, and on my floppy drive. But I used this floppy as a test, to see if I could recover the data on it. First i tried GNU ddrescue, since it is (supposedly) is improved compared to dd_rescue.

tingo@kg-t2$ ddrescue -n /dev/fd1 ./210628F01-XX-01D.image.5 ./210628F01-XX-01D.image.5.log


Press Ctrl-C to interrupt
Initial status (read from logfile)
rescued:         0 B,  errsize:       0 B,  errors:       0
Current status
rescued:         0 B,  errsize:   1261 kB,  current rate:        0 B/s
   ipos:     65536 B,   errors:       1,    average rate:        0 B/s
   opos:     65536 B,     time from last successful read:       0 s
Finished                   
tingo@kg-t2$ ddrescue -n /dev/fd1 ./210628F01-XX-01D.image.5 ./210628F01-XX-01D.image.5.log


Press Ctrl-C to interrupt
Initial status (read from logfile)
rescued:         0 B,  errsize:   1261 kB,  errors:       1
Current status
rescued:         0 B,  errsize:   1261 kB,  current rate:        0 B/s
   ipos:         0 B,   errors:       1,    average rate:        0 B/s
   opos:         0 B,     time from last successful read:       0 s
Finished

Unfortunately, it looks like GNU ddrescue simply doesn't work on this system at all - it could not read even one record from the floppy.

So I tried dd_rescue. It did better - it managed to read data from the floppy, but it read even less than a simple 'dd' did. And it gave these errors:

dd_rescue: (info): ipos:     31290.5k, opos:     31290.5k, xferd:     31290.5k
                *  errs:  60661, errxfer:     30330.5k, succxfer:       960.0k
             +curr.rate:      650kB/s, avg.rate:      265kB/s, avg.load: 15.2%
dd_rescue: (warning): /dev/fd1 (31290.5k): Invalid argument!

repeated many, man times. I'm not sure why it says "Invalid argument!". After all these attempts, there was a visible line on the coating of the floppy itself. I'm not sure, but I do not think it was there before I tried data recovery o this floppy. --Torfinn (talk) 20:42, 27 July 2016 (UTC)