What kind of drive is it? I have had good luck getting seagates to remap, on my 3tb WD Red drive with bad sectors the drive does not seem to remap them as easily. So far I have a lot of repeat bad sectors, but only 1 has remapped, even thought I am given the drive a lot of chances to remap the sectors. On Tue, Feb 6, 2018 at 4:02 PM, Marc MERLIN <marc@xxxxxxxxxxx> wrote: > On Wed, Feb 07, 2018 at 08:51:15AM +1100, Adam Goryachev wrote: >> I think instead of reading the sector from the drive and relying on the >> drive to determine the correct data (it's already telling you it can't). > > Just on that point, it's not that simple. A drive will only try to read the > data a few times before giving up and marking the sector as pending a > re-write with new data (so that it can be re-mapped). > You can however re-read it in different ways and sometimes get the data > back, which _should_ then cause an immediate re-writing of the data on a new > block and turn the pending into a reallocated block > However, this does not seem to have happened on my drive, either because the > bad data didn't really get read by hdparm --read-sector, or because the > firmware isn't doing its remapping job, or something else I don't understand > >> What you need to do is find out where on md7 drive x sector y maps to >> and read that sector from md7, which will get md to (possibly) notice >> the read error, and then read the data from the other drives, and then >> re-write the faulty sector with correct calculated data (or do the >> resync on that area of md7 only). > > Yeah, I got that part. > >> So try setting something like 1287000000 * 4 as the start of the resync >> up to 1288000000 * 4 and see if that finds and fixes it for you. >> >> If nothing else, it should finish fairly quickly. You might need to >> start earlier, but you could just keep reducing the "window" until you >> find the right spot. Or, someone who knows a lot more about this mapping >> might jump in and answer the question, though they might need to see the >> raid details to see the actual physical layout/order of drives/etc. > > I did however (indeed) miss that I can narrow the check range, so I'll try > playing with that until I can narrow it down to the right bit. > > I'm still curious as to why the hdparm bit didn't work, but oh well at this > point. > > Thanks, > Marc > -- > "A mouse is a device used to point at the xterm you want to type in" - A.S.R. > Microsoft is to operating systems .... > .... what McDonalds is to gourmet cooking > Home page: http://marc.merlins.org/ > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
