Image corruption on Windows (defraggers, optical disks)
Posted: Sat Oct 21, 2017 7:49 pm
Context: running Windows 7 Pro on an i7 3770K.
The following questions may seem dumb. But I just had a failure, and while BIBM's imaging feature usually makes such occurrences a non-issue, this time I experienced the nasty shock of finding that not just one but two of my trusty Terabyte images were corrupt. Their loss has been a serious problem because with HD space at a premium, I ration my backups carefully--I don't keep very many, and each one serves as a major milestone in system development. Mainly I depend on registry backups to deal with system problems, and I have a good registry backup system with a custom tbscript, and that takes care of nearly everything that comes my way. So when I have to resort to an image, I need it bad. This has been a good system for years, but being cut off at the knees by the corruption of my two most important images has really hurt. I had to go back to an image that is 5 years old (thankfully at least that one was still valid). As far as I can recall this has never happened with even one Terabyte image before, let alone two at the same time, and I'm a (very) long-time user, since just a few years after BING was first released. And I always choose to validate as part of the image process, so these were good when taken.
So I need to make sure of a couple of things. Two questions:
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1
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Does the Windows native defragmenter fall under the same onus as others (e.g. Puran Utilities or MyDefrag) re Terabye image corruption?
https://www.terabyteunlimited.com/kb/article.php?id=151 says to disable third-party defragmenters, then continues, "Defragment utilities can also cause corruption if the system RAM is bad. The files are no good once they are corrupted by a defragment utility." The way the paragraph is worded, it remains unclear whether Windows's defragmenter, which presumably is not "third party" as it is native to the OS, can also cause corruption if there is bad RAM.
I probably do have problematic RAM. Ran Windows memory test but it hung at 60% of the way through, which is probably a bad sign. Haven't bothered running memtest yet as it doesn't really matter--I cannot afford to replace RAM right now, and won't be able to for the next three or four months. So as long as the system boots and I can use it, it'll have to go on with bad RAM for a while. Thus I badly need to know if the native Windows defragger has the same effect with bad RAM as third-party utilities. That way if I must defragment the drive on which the images reside, I can move them beforehand, then copy them back after I'm done.
EDIT: I also use Puran's DiskFresh to realign sectors every once in a while . Will this have the same effect as a third-party defragment utility?
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2
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Are Terabyte images especially "fragile" on optical disks--i.e. the least little problem makes them unuseable? Or is BIBM especially sensitive to problems with optical disks? Or something similar?
The second of my two mainstay images which turned out to be corrupt was a worse shock than the first. This second one was on bootable DVD. The disk starts the imaging process but then stalls a little over halfway through (always at exactly the same 9-minute point; I attempted to run it 3 times) with a message that it can't read the disk. Subsequently I validated it, of course, and the validate failed. Didn't bother validating prior to attempting restoration because as I said before, I always validate when the image is taken, so it was good at that time. The DVD is scuffed but has no scratches. It's certainly not half so bad as audio CDs I have which have many scratches but still play, or old software installation disks that still run fine with lots of scratches (thank heavens, as I unfortunately need some of them now), or even old data backups on DVD--made back when putting all your data on one or two DVDs was still possible--with lots of scratches but which can still be read.
This is an important issue, as I've always considered my Terabyte optical images to be secured from the vagaries of hard-disk problems. My old BING CDs saved my neck on multiple occasions. Terabyte opticals are my buck-stops-here ultimate safety net...except that they sure weren't this time.
BTW, this image was made using BIBM 1.16. Would 1.41, which I've just downloaded, be better for optical disks?
The following questions may seem dumb. But I just had a failure, and while BIBM's imaging feature usually makes such occurrences a non-issue, this time I experienced the nasty shock of finding that not just one but two of my trusty Terabyte images were corrupt. Their loss has been a serious problem because with HD space at a premium, I ration my backups carefully--I don't keep very many, and each one serves as a major milestone in system development. Mainly I depend on registry backups to deal with system problems, and I have a good registry backup system with a custom tbscript, and that takes care of nearly everything that comes my way. So when I have to resort to an image, I need it bad. This has been a good system for years, but being cut off at the knees by the corruption of my two most important images has really hurt. I had to go back to an image that is 5 years old (thankfully at least that one was still valid). As far as I can recall this has never happened with even one Terabyte image before, let alone two at the same time, and I'm a (very) long-time user, since just a few years after BING was first released. And I always choose to validate as part of the image process, so these were good when taken.
So I need to make sure of a couple of things. Two questions:
=
1
=
Does the Windows native defragmenter fall under the same onus as others (e.g. Puran Utilities or MyDefrag) re Terabye image corruption?
https://www.terabyteunlimited.com/kb/article.php?id=151 says to disable third-party defragmenters, then continues, "Defragment utilities can also cause corruption if the system RAM is bad. The files are no good once they are corrupted by a defragment utility." The way the paragraph is worded, it remains unclear whether Windows's defragmenter, which presumably is not "third party" as it is native to the OS, can also cause corruption if there is bad RAM.
I probably do have problematic RAM. Ran Windows memory test but it hung at 60% of the way through, which is probably a bad sign. Haven't bothered running memtest yet as it doesn't really matter--I cannot afford to replace RAM right now, and won't be able to for the next three or four months. So as long as the system boots and I can use it, it'll have to go on with bad RAM for a while. Thus I badly need to know if the native Windows defragger has the same effect with bad RAM as third-party utilities. That way if I must defragment the drive on which the images reside, I can move them beforehand, then copy them back after I'm done.
EDIT: I also use Puran's DiskFresh to realign sectors every once in a while . Will this have the same effect as a third-party defragment utility?
=
2
=
Are Terabyte images especially "fragile" on optical disks--i.e. the least little problem makes them unuseable? Or is BIBM especially sensitive to problems with optical disks? Or something similar?
The second of my two mainstay images which turned out to be corrupt was a worse shock than the first. This second one was on bootable DVD. The disk starts the imaging process but then stalls a little over halfway through (always at exactly the same 9-minute point; I attempted to run it 3 times) with a message that it can't read the disk. Subsequently I validated it, of course, and the validate failed. Didn't bother validating prior to attempting restoration because as I said before, I always validate when the image is taken, so it was good at that time. The DVD is scuffed but has no scratches. It's certainly not half so bad as audio CDs I have which have many scratches but still play, or old software installation disks that still run fine with lots of scratches (thank heavens, as I unfortunately need some of them now), or even old data backups on DVD--made back when putting all your data on one or two DVDs was still possible--with lots of scratches but which can still be read.
This is an important issue, as I've always considered my Terabyte optical images to be secured from the vagaries of hard-disk problems. My old BING CDs saved my neck on multiple occasions. Terabyte opticals are my buck-stops-here ultimate safety net...except that they sure weren't this time.
BTW, this image was made using BIBM 1.16. Would 1.41, which I've just downloaded, be better for optical disks?