Hard Drives
Aug. 22nd, 2007 09:54 pmAttn: Geeks.
If a hard drive works alright in electronic terms but has bad sectors, specifically about 17 of them at the end of the disk, is there a way to fix it? Or are they junk?
These are Seagate Barracuda 19.8GB SCSI drives. There are many of them so it is worth knowing if there is a reliable or even tenuous fix. Otherwise they shall be scrapped for magnets.
If a hard drive works alright in electronic terms but has bad sectors, specifically about 17 of them at the end of the disk, is there a way to fix it? Or are they junk?
These are Seagate Barracuda 19.8GB SCSI drives. There are many of them so it is worth knowing if there is a reliable or even tenuous fix. Otherwise they shall be scrapped for magnets.
no subject
Date: 2007-08-22 09:07 pm (UTC)Would these be the type of drives that come in towers, which often used to be used as RAID arrays? Used to get a lot of those as office surplus; not so common now that SCSI drives seem to be becoming obsolescent rather rapidly.
no subject
Date: 2007-08-22 09:12 pm (UTC)Usually a SCSI drive will detect a bad sector on its own and will remap that sector to another (spare) place on the drive. This is completely translucent to the user, so unless you run out of spare sectors you should never notice a bad sector on the drive.
Given the above and that all of them seem to be at the end of the disk I suspect that there is something else wrong with the disks (or with their formatting)
no subject
Date: 2007-08-22 09:28 pm (UTC)On a harddrive, bad blocks happen all the time. There's always physical defects on a harddrive platter, and there's always individual blocks that
go bad over time. In order to prevent data loss, and in order to prevent grave accidents, IDE (both SATA as well as PATA) and SCSI drives keep a list of spare sectors at hand. If a block is going bad -which can often be detected before there's no hope of recovery-, it is marked as such, and it is replaced with a sector from the spare sector list, and disaster has been averted.
However, this will of course only work as long as there are still spare sectors left. When a drive runs out of spare sectors, there's nothing to replace bad blocks with, and this is when you'll suddenly start noticing them.
You could try a low-level format (SeaTools Enterprise edition, linkie (http://www.seagate.com/ww/v/index.jsp?locale=en-US&name=SeaTools:_Enterprise_Edition&vgnextoid=8f1bd20cacdec010VgnVCM100000dd04090aRCRD),
DOS/Linux only). With a bit of luck this will allow you to map the bad blocks and add new spare sectors to the spare sectors list, at the expense of a barely noticable decrease in capacity. Additionally, you'll loose all the data on the disk, so backup first. However, it's very questionable as to whether this is a good idea. Chances are big that the reason the drive currently thinks it has a lot of bad sectors are because the analog drive electronics are slowly failing. It's not completely dead yet, but it has more difficulties dealing with things. Chances are big that you'll freshly revived disks will develop new bad blocks within a short time, possibly causing data to be lost. It'll be never be really reliable.
Diskspace is cheap, these days - about 25 pence a GB. Are you sure it's worth it? I'd junk them.
no subject
Date: 2007-08-23 12:27 am (UTC)no subject
Date: 2007-08-23 12:28 am (UTC)no subject
Date: 2007-08-23 04:54 am (UTC)But have no doubt, that drive is on its way out. Secure your critical data ASAP.
no subject
Date: 2007-08-23 09:06 am (UTC)no subject
Date: 2007-08-23 02:51 pm (UTC)When my scsi disk went bad, I sent it in for RMA and approx. 2 weeks later I had a replacement disk (did have some trouble getting the RMA, had to convince the person on the other end that the shrieking high pitched noise was actually there). The replacement disk I received had the same capacity, but was half the height. Usually, less height is nice for mounting a disk, but you'd want to check in advance if you really require the disk to be the same height.
I don't know how reliable maxtor disks are, even though the 4 disks I have at the moment are all maxtor: I bought them when the harddisk devision from Quantum was taken over by Maxtor, so my disks are still Quantum's design. They work fine though.
no subject
Date: 2007-08-23 07:58 pm (UTC)Backup! Backup! Backup!
no subject
Date: 2007-08-25 11:38 pm (UTC)