On Thu, 2003-09-25 at 15:25, Justin Findlay wrote: > >From the mists of youth I remember a MS-DOS based utility that formatted > and defragmented the hard drive. On one occasion I remember it marking > some few random blocks as "bad", and then later after reformatting the > drive they seemed to have been repaired by the reformat. My explanation > at the time was that reformatting applied some magnetic field onto the > disks which brought things back into order. What actually is a "bad" > block? Is it possible to "repair" it with such a savvy reformatting > utility?
What you are referring to is "low-level" formatting. This was used back in the day to redo track markers and so forth on the disk. I actually did manage to repair several disks with it. However, I don't think they recommend lowlevel formatting of new IDE disks these days. Can't remember the reasons. > > My 10 month old Western Digital drive has 3 contiguous bad blocks. They > are deep enough inside the root partition that they will probably not > cause any trouble for a while. Can I find a magical tool that will > instruct the drive to fix them? Or should I just wrap a partition around > them, and call it the partition of death. Most drives only have a one year warranty, so if you're in your 10th month, I would just get it replaced on warranty. Otherwise you'll just have problems. There are no other magical tools or solutions really. Stop-gap measures, but really you're asking to lose data. By the way, on my 4 one-terrabyte IDE RAID-5/1 arrays (there are 4 arrays total), I expect to lose a few of the 180 GB disks every year. Michael > > > On Thu, 25 Sep 2003, Matthew J. Probst wrote: > > > I would agree with Stuart and Evan. All modern IDE drives have what SCSI > > drives have had from the onset: bad block remapping. They have a pool of > > X spare blocks that are not directly usable by the OS. When they read a > > block and discover a read error (such as parity) they will take a block > > from their spare pool and map it over the actual block. (It attempts to > > copy the old data to the new block). Subsequent reads and writes will go > > to the new block. > > > > With that being said, if the OS actually sees a bad block, this is > > generally representative of the spare block pool being completely used up > > (due to some many bad blocks). It can also be due to head problems or > > parity checking problems. Either way, it means the drive is close to the > > end of its life. > > > > Given the bad block remapping, most modern file systems have come to > > expect a virtually 100% error free drive and generally don't know how to > > deal with actually seeing bad blocks. Some deal better, though. Ext2/3 > > have better bad block handling than FreeBSD's UFS (which can't deal with > > bad blocks at all). > > > > -matt > > > > On Wed, 24 Sep 2003, Stuart Jansen wrote: > > > > > On Wed, 2003-09-24 at 21:01, Jeremy S Robertson wrote: > > > > I'm now trying a new installation of redhat on my desktop. However, the > > > > installation detected bad blocks and aborted the installation. > > > > > > > > What should I do to mark the bad blocks so I can install? > > > > > > My personal opinion (experience) is that bad blocks are a sign it's time > > > to get a new drive. :-( > > > > > > If you're really insistent, you could format the drive by hand. I won't > > > say more than > > > > > > mke2fs -c > > > > > > As you're taking the responsibility for your actions, a little reading > > > of man pages is in order. > > > > > > -- > > > Stuart Jansen <[EMAIL PROTECTED], AIM:StuartMJansen> > > > > > > #define FALSE 0 /* This is the naked Truth */ > > > #define TRUE 1 /* and this is the Light */ -- mailto.c > > > > > > > _______________________________________________ > > newbies mailing list > > [EMAIL PROTECTED] > > http://phantom.byu.edu/cgi-bin/mailman/listinfo/newbies > > > > > _______________________________________________ > newbies mailing list > [EMAIL PROTECTED] > http://phantom.byu.edu/cgi-bin/mailman/listinfo/newbies _______________________________________________ newbies mailing list [EMAIL PROTECTED] http://phantom.byu.edu/cgi-bin/mailman/listinfo/newbies
