fsck unable to read disk sectors

[Alexander Best]

the problem is getting more awkward.

if i do `fsck /dev/label/rootfs` fsck complains that it cannot read a
specific sector of my hdd as i mentioned before. if i run fsck on the
device node directly using `fsck /dev/ada0p3` however, fsck succeeds.
what i did was to boot into single user mode with / being mounted read
only. for some reason however fsck will check /dev/label/rootfs in
write mode, but if i want fsck to check ada0p3 it will only do so in
read mode.

this looks like something is really broken. right now the only way to
get the clean flag set on my hdd is to boot from a livefs cd and then
run `fsck /dev/ada0p3` (again: `fsck /dev/label/rootfs` will NOT
succeed).

this is the output of `glabel status` btw:

                                     Name  Status  Components
                               label/boot     N/A  ada0p1
gptid/e52df583-e446-11de-bb92-000fb58207c8     N/A  ada0p1
                               label/swap     N/A  ada0p2
                             label/rootfs     N/A  ada0p3

cheers.

On Tue, Mar 30, 2010 at 2:08 AM, Paul B Mahol <onemda at gmail.com> wrote:
> On 3/29/10, Alexander Best <alexbestms at wwu.de> wrote:
>> hi there,
>>
>> when doing fsck on my / fs i get this error:
>>
>> "Cannot Read BLK. 471617640" and "The Following Disk Sectors could not be
>> read: 471617643". after this message the partition gets marked dirty.
>>
>> i performed the following steps to verify the problem:
>>
>> 1) dd if=/dev/ada0 of=/dev/null bs=1m
>> 2) fsck / under freebsd 7
>> 3) mount -u -o snapshot /.snap/snapshot1 / && fsck_ffs /.snap/snapshot1
>>
>> all three steps showed no problem with that harddrive whatsoever. also
>> smartd
>> doesn't complain about anything.
>>
>> i'm running HEAD (r205860) on amd64.
>>
>> this is the output of `dmesg -a|grep ada0`:
>>
>> ada0 at ahcich2 bus 0 scbus3 target 0 lun 0
>> ada0: <SAMSUNG SP2504C VT100-50> ATA-7 SATA 2.x device
>> ada0: 300.000MB/s transfers (SATA 2.x, UDMA6, PIO 8192bytes)
>> ada0: Command Queueing enabled
>> ada0: 238474MB (488395055 512 byte sectors: 16H 63S/T 16383C)
>
> Last time I tried ahci on dead disk it did not complained at all
> (usually I get dead LBA listed on console).
>



-- 
Alexander Best