With disks, the blocks can change. There can be any number of reasons for this, from the actual physical platters going bad to the read heads not functioning properly, or the memory on the disk going bad. SSD is a different story, in my experience when it begins to go the behavior becomes really erratic and inconsistent. You could try replacing cables, but you are probably looking at replacing the disk.
On Sat, Jan 6, 2018 at 9:12 PM STeve Andre' <and...@msu.edu> wrote: > When you enter the realm of hardware errors, anything can happen. If > you are lucky you will see the same hard and soft errors every time you > cross a bad sector, but I have seen many cases wildly varying block > numbers on really sick disks. And yes, bad cables and USB interfaces > can be a problem too. Try wiggling the cable disk the disk stable and > see if you can produce errors. > > Try doing a read with that USB hardware on another disk, too. That will > tell you something. I'll bet that the disk is bad. If it stops > producing errors, don't forgive it! Get a new one. > > --STeve Andre' > > On 01/06/18 21:45, Maximilian Pichler wrote: > > Hi, > > > > I'm running fsck on an external USB hard drive, using OpenBSD 6.2 > > inside VirtualBox on MacOS. > > > > On each run it gives a handful of "CANNOT READ: BLK ..." messages, but > > the block numbers reported are different (!) each time. > > > > If the disk is damaged, shouldn't the problematic blocks be > > consistent? Does this point to a communication problem with the disk > > (e.g. faulty USB cable)? Or is this a hopelessly unstable situation > > given the general screwiness of USB over VirtualBox/Mac OS...? > > > > Also, does answering "y" to "CANNOT READ" modify the disk contents? > > > > Thanks for any insights! > > > > Max > > > > > > xhci0 at pci0 dev 12 function 0 "Intel 7 Series xHCI" rev 0x00: apic 2 > int 20 > > usb0 at xhci0: USB revision 3.0 > > uhub0 at usb0 configuration 1 interface 0 "Intel xHCI root hub" rev > > 3.00/1.00 addr 1 > > umass0 at uhub0 port 9 configuration 1 interface 0 "Seagate Expansion" > > rev 3.00/0.00 addr 2 > > umass0: using SCSI over Bulk-Only > > scsibus4 at umass0: 2 targets, initiator 0 > > sd0 at scsibus4 targ 1 lun 0: <Seagate, Expansion, 9300> SCSI4 0/direct > fixed > > sd0: 3815447MB, 512 bytes/sector, 7814037167 <(781)%20403-7167> sectors > > > > $ doas fsck /dev/sd0a > > ** /dev/rsd0a > > ** Last Mounted on /home/max/mnt > > ** Phase 1 - Check Blocks and Sizes > > > > CANNOT READ: BLK 4235468160 <(423)%20546-8160> > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > > > CANNOT READ: BLK 4128081280 <(412)%20808-1280> > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > CANNOT READ: BLK 4194986880 <(419)%20498-6880> > > CONTINUE? [Fyn?] y > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > ** Phase 2 - Check Pathnames > > > > CANNOT READ: BLK 4195146384 <(419)%20514-6384> > > CONTINUE? [Fyn?] y > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > ** Phase 3 - Check Connectivity > > ** Phase 4 - Check Reference Counts > > ** Phase 5 - Check Cyl groups > > 614222 files, 408012667 used, 76524122 free (3658 frags, 9565058 > > blocks, 0.0% fragmentation) > > > > MARK FILE SYSTEM CLEAN? [Fyn?] y > > > > > > ***** FILE SYSTEM WAS MODIFIED ***** > > > > > > $ doas fsck -f /dev/sd0a > > ** /dev/rsd0a > > ** File system is already clean > > ** Last Mounted on /home/max/mnt > > ** Phase 1 - Check Blocks and Sizes > > > > CANNOT READ: BLK 4236615424 <(423)%20661-5424> > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > ** Phase 2 - Check Pathnames > > > > CANNOT READ: BLK 3732315520 > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > > > CANNOT READ: BLK 4161885792 > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > > > CANNOT READ: BLK 4201995728 > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > > > CANNOT READ: BLK 4202008160 > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > > > CANNOT READ: BLK 4202013680 > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > ** Phase 3 - Check Connectivity > > ** Phase 4 - Check Reference Counts > > ** Phase 5 - Check Cyl groups > > > > CANNOT READ: BLK 5011229824 > > CONTINUE? [Fyn?] y > > > > THE FOLLOWING DISK SECTORS COULD NOT BE READ: > > 614222 files, 408012667 used, 76524122 free (3658 frags, 9565058 > > blocks, 0.0% fragmentation) > > > > > > -- There's no place like 127.0.0.1
