On Sunday 27 Jul 2014 17:50:49 meino.cramer@gmx.de wrote:

> I executed the mkswap/dd combo a several times today. Since I have
> no logs I repeated again. Here are the results:
> 
> solfire:/home/user>mkswap -L swap -f -c /dev/sda2
> 1 bad page
> mkswap: /dev/sda2: warning: wiping old swap signature.
> Setting up swapspace version 1, size = 6291448 KiB
> LABEL=swap, UUID=e742c0a6-862c-41e9-be4b-698b33c5a236
> solfire:/home/user>dd if=/dev/zero of=/dev/sda2 bs=512 conv=notrunc
> dd: error writing ‘/dev/sda2’: Input/output error
> 1669369+0 records in
> 1669368+0 records out
> 854716416 bytes (855 MB) copied, 28.4799 s, 30.0 MB/s
> [1]    24047 exit 1     dd if=/dev/zero of=/dev/sda2 bs=512 conv=notrunc
> solfire:/home/user>

Ahh!  This is a different result to what you showed previously, unless you 
chopped off the output last time.  It now shows that it was able to write:

 1669368 x 512 = 854,716,416 bytes 

out of a total sda2 partition size of 6.29 GiB.

> I am a little anxious about the hdparm command...
> For me it is unclear what sector is meant:
> 
> smartclt says:
> Num  Test_Description    Status                  Remaining  LifeTime(hours)
>  LBA_of_first_error # 1  Selective offline   Completed: read failure      
> 90%     14500         4288352511
> 
> From a previous posting I learned that "LBA" in this case is the byte
> counter.
> 
> The sector is therefore 4288352511/512=8375688

OK, let's not confuse ourselves:  LBA counting starts from zero.

Therefore, if you subtract the start of the sda2 partition it becomes:

4288352511 - 104448 = 4288248063 / 512 = 8,375,484.5 bytes, within the sda2 
partition.

Unless my maths failed me above, I can't say I understand why dd bailed out 
after writing 854,716,416 bytes, but smartctl failed earlier than that reading 
just 8,375,484.5 bytes.  Perhaps dd can write further, than what smartctl can 
read without error, because these are two different mechanisms - but I am 
guessing wildly.  :-)

Someone more knowledgeable should chime in here.

PS. I'm copying you in just in case this is lost in your Inbox - I had to 
resend it because I used the wrong From address by mistake and I suspect it 
never made it to the list.
-- 
Regards,
Mick