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Re: Backup--OT

Really? I haven't seen incorrect
copying for decades.


Then you probably haven't been looking for it. Incorrect copying is hard
to spot when the OS or program does not report it. You just assume that
your 100GB of user files is perfectly copied in the absence of any notice
to the contrary. Yet I have found over the years that the occasional file
gets degraded to the point of unusability. Obviously, I am only able to
check a tiny fraction of my files.


Here's some general information on the problem:


http://www.techsupportalert.com/Brilliant-File-Integrity-Verification-Utility; eudora="autourl">
http://www.techsupportalert.com/Brilliant-File-Integrity-Verification-Utility



and here's a highly rated disk duplicator with some form of verfication;
however it is several times more expensive than the one you are using,
and I have not yet discovered what method or choice of verification
methods (hash or bit-by-bit) it uses:


https://www.diskology.com/djstandard.html; eudora="autourl">
https://www.diskology.com/djstandard.html


The problem with disk verification is that it is slow; and every
technique used to speed it up also compromises its accuracy.



He recommends RAID. I was
wondering if that wouldn't be a better solution than the disk duplicator.
But the RAID enclosure would have to connect by some means to the
computer, and wouldn't that slow things down?


When you say RAID here, you probably mean RAID 1 (two disks that
simultaneously mirror one another). That is the safest though the least
efficient (in terms of disk space) form of RAID.


There is no requirement whatever for a RAID enclosure. In a
desktop, you simply use a RAID controller, or many motherboards
have them built in. There are a few laptops with space for two drives
and with hardware RAID capability but these are growing scarce.
For a laptop that will permit two disk drives but that does not have a
hardware RAID controller, either MacOS or Windows will do software RAID
1.


Performance hit with hardware RAID can be negligible.


Running a system from an external drive without loss of speed would
require a lot of high-end hardware and specialist intervention. I would
think a Thunderbolt connexion would help.


RAID 1 itself is not a perfect guarantee against data corruption - - see
the Wikipedia RAID article which raises a number of important issues.
(And note that while the simultaneous aging of mechanical hard drives is
raised, the simultaneous aging of SSDs is just as likely to bring
problems.)


In sum, I feel that any collection of personal data at any time will
inevitably reflect some data corruption. I think the best defense is to
hold time capsules: periodic backups on M-Discs DVDs or blu-rays. If a
file is found to be corrupt in 2014, it may be possible to find an
incorrupt version on, for example, a 2012 M-Disc. (Or even, if you're
very lucky, conventional optical media.)


The problem of detecting what files, in a lifetime's aggregation of user
files, are corrupt, seems to be nearly insoluble. That's why I find the
time-capsule approach attractive.





--Harry





For anyone who wants further
fuel for storage paranoia, Robin Harris's articles on NTFS corruption and
SSD corruption are good starting points:


http://www.zdnet.com/blog/storage/how-ssds-can-hose-your-data/1423; eudora="autourl">
http://www.zdnet.com/blog/storage/how-ssds-can-hose-your-data/1423



http://www.zdnet.com/blog/storage/how-microsoft-puts-your-data-at-risk/169; eudora="autourl">
http://www.zdnet.com/blog/storage/how-microsoft-puts-your-data-at-risk/169



(further searches will reveal how Apple missed the boat on supporting a
reliable file system; also his stuff on MDISC which apparently finally
has a '1000-year' blu-ray - - topics discussed on this list last
year)


At 20/04/2014 19:24, you wrote:





That's interesting - - I didn't
think you'd be easy to convince. And as I say, you've gotten me to doubt.
I am assuming that there is some kind of verify
mechanism?


Just that I put the backup drive in the machine and it boots.





Regarding ShadowProtect, I just
now had a need accidentally downloaded something from Linkbury which is
one of the most annoying things ever. I had backed up an hour ago so I
thought it would be a cinch to restore from ShadowProtect. But, on my new
Dell system with the 8 partitions and heaven only knows what sort of
BIOS, I simply cannot get the recovery environment to work. It will boot,
via a USB external CD, but then it hangs. There are many ways around
this: I could just do it all on another system, but I am disturbed that I
cannot do it on the host system. This is the first time I have had a
problem with ShadowProtect. Harry, you brought it upon
me!


The Shadow knows!





At 18/04/2014 17:53, you
wrote:


Bill,


You've convinced me not to use any software solution. The best I can
think of in using the disk duplicator is to get or fabricate some kind of
cable that would allow me to keep the SSD *outside* of the computer. I've
searched for these, but I don't think they exist. The idea would be to
plug one end of the cable inside the laptop where the SSD connects and
the other end of the cable to the SSD. Its purpose would only be to avoid
having to unscrew the little door on the Thinkpad inside of which the SSD
normally lives. Ideally the cable extender would be a Y-shaped one, so
that the SSD would always be plugged into both the computer and the drive
duplicator.


As to the one I use, it's available for $51 from newegg:


http://www.newegg.com/Product/Product.aspx?gclid=CJPqpNy_6r0CFQ2hOgoda2oAJw&Item=N82E16817422030&nm_mc=KNC-GoogleAdwords&cm_mmc=KNC-GoogleAdwords-_-pla-_-Hard+Drive+Enclosures-_-N82E16817422030&ef_id=U0QBfgAABVdzqSDN:20140418165301:s; eudora="autourl">
http://www.newegg.com/Product/Product.aspx?gclid=CJPqpNy_6r0CFQ2hOgoda2oAJw&Item=N82E16817422030&nm_mc=KNC-GoogleAdwords&cm_mmc=KNC-GoogleAdwords-_-pla-_-Hard+Drive+Enclosures-_-N82E16817422030&ef_id=U0QBfgAABVdzqSDN:20140418165301:s



Regards,

Harry



Hi Harry,


1. The files that ShadowProtect creates are not the image itself. (You
will often choose to use some degree of compression.) They are the data
SP uses to create the image on the target media. I don't know how to
explain it any better than that - - it is confusing. I am not confident
that I am using the vocabulary correctly.


2. So: let's say you have a hard drive that has failed, and you need to
restore your system to a new hard drive from the SP backup you made an
hour before the crash.


You need the SP program to take your backup data and write the image onto
the new hard drive. I have done this in two ways.


a. by booting the SP disk on my target computer's CD (on a new system you
could just as well boot with a USB stick), and restoring to new hard
drive from an external with the SP data


or


b. by using a different computer that has SP installed. On this computer,
I will have two external drives. Drive 1 is the SP backup; Drive 2 is the
blank you want to image. In this case, I tell the SP program to restore
Drive 2 from Drive 1. (Physically speaking, I do not place Drive 2, the
new hard drive, into an actual enclosure; rather, I use Newertech's
Universal Drive Adapter which connects, without any enclosure or fuss,
any drive to a USB 2/3 port.)


You've forced me to think about this deeply unpleasant subject again, and
I offer these observations:


1. SP seems to work. By contrast, I have not been happy with more or less
recent versions of Ghost and Acronis. I was particularly upset when Ghost
lost the ability to live clone one hard drive to another - - perhaps that
has been fixed? Apart from that, both Ghost and Acronis have always been
buggy for me.


2. There definitely are gotchas in SP. One of its characteristics is that
there are some partitions that will only backup on a full backup. They
will not work on an incremental backup job. Therefore, if you don't want
to see a backup failed message, you have to remove those partitions from
the incremental backup job. I don't like this.


3. More and more, I can see the point in using a hardware-only solution
such as you have, and would be grateful if you pointed me to the website
for the product. I do strenuously object to the requirement that you have
to remove the source drive from the computer each time you want to do a
backup, but if this is the price one has to pay for total duplication
security, I might be willing to do it on an infrequent basis.


4. In addition to SP, I use
http://www.memopal.com/
for continuous-to-cloud backup of data files. I have found this works
very well so far. One thing I like about this system is that it backs up
as soon as the file is saved to host disk, and saves multiple versions.
This feature has saved my butt on many occasions. However, it would be
tiresome to have to do a full restore of data files from this
service.


5. Participating in this thread and facing my current problems with SP
and my 7-partition 'plain vanilla' new system, I realize that, in order
to avoid error messages, I need to schedule two separate
backups.


a. A non-incremental weekly backup of the entire hard drive, including
all the invisible partitions.


b. An incremental hourly backup of the only partition (i.e. 'c') which
actually has any changed data.


I have not done this yet, so, with my current system schedule, SP will
report success for my weekly, full backups, but will report failure for
the incremental backups. It is important to the note that the incremental
backups have not failed. If I go into the 'details' tab, I will discover
that the incremental backup of my 'c volume' - - which is the only volume
on which any data has change - - has been successful. The parts of the
job that reportedly 'fail' are some of the hidden partitions; and the
error message always is the same: incrementals not supported on this
volume.


I hope this has been helpful. Showing is better than telling, so I
suggest downloading a trial copy from the storagecraft website.


Again, this only follows my own experience. I started using SP about five
or six years ago, on v. 3, after reading Ed Mendelson's review in PC Mag.
Ed is not just any magazine reviewer. This polymath is also Trilling
Professor at Columbia and Auden's executor and, of course, a notorious
WP/DOS maven. I believe he is the most knowledgeable and incorruptible of
all the computer magazine writers.
https://en.wikipedia.org/wiki/Edward_Mendelson; eudora="autourl">
https://en.wikipedia.org/wiki/Edward_Mendelson .


At 18/04/2014 03:22, you wrote:


Bill,


This sounds great. But I'm confused about one thing. If the image file is
bootable, what's doing with the CD? You say, "in case of
disaster." Meaning what? That your regular hard drive won't boot? I
don't fully trust booting from a CD (have had problems: the Lenovo
Thinkpad I have doesn't have an internal CD drive, so have to use an
external USB CD drive and change the boot order, but it doesn't always
work--something about the unreliability of non-powered USB CD drives, I
think.


So why can't you boot from the bootable image? And how specifically would
you go from invoking SP on another computer to getting a drive to insert
in the now defunct computer?


Thanks so much,

Harry



Harry, I am totally with you in
the idea that the only Windows backup worth having is a complete bootable
one. However, I do it differently: automated and in software. I use
ShadowProtect. This creates a bootable image file (I split it into 640MB
segments) that is incrementable and automatable (I do a full backup every
week; an incremental every 3 hours).


So how do you get a bootable drive out of this? In case of disaster, you
boot up with a ShadowProtect CD (or simply invoke ShadowProtect on
another computer) and restore your image to your target hard
drive.


The result will be a perfect duplicate.


I have done this several times with complete success. ShadowProtect is
the only such system that has ever worked for me. (Acronis is not a patch
on it.) I have complete confidence in it.


Are there any gotchas? I would say that you have to watch the numerous
hidden partitions (more and more!) that modern computers are beginning
toi have. (For example there are seven partitions on my plain vanilla
Dell XPS 15 late 2013. Why so many? Heaven knows.) Once or twice, I have
lost one of these partitions, but it has not affected me in any visible
way.


SSDs are great but they can benefit from maintenance and they do in the
end fail.


Why not use both? Continue to use the hardware solution but only once
every couple of months? Meanwhile use the software solution regularly.
You will then have the convenience of up-to-the-minute backups (as long
as the backup drive is connected of course).


These images are complete total, total, total duplicates of your hard
drive state. There is no need to worry about losing any value
whatever.


NB: This is just one user's experience over the past few years.




At 17/04/2014 22:11, you wrote:


I have a technical question that
maybe one or more of you would be so kind as to help with.


I've been bitten by disaster too many times not to be very concerned with
backup. I have now what is the ideal solution, except for one flaw: I
take the SSD drive out of my Lenovo Thinkpad (fairly easy to do, but
requires unscrewing one screw), and put it with the backup drive into a
toaster-like drive-duplicator from Aluratek that duplicates the SSD,
sector by sector, onto the backup drive. The result is a completely
substitutable, bootable dupe of my SSD (which I then replace in my
Thinkpad).


The only problem is that I can't do this, of course, as a scheduled
task.


I am doing physical drive duplication because via software, you can't
produce a bootable drive. But is making a clone image good enough? I have
tried Acronis, EaseUS, and Carbonite for making "images," but
they aren't bootable. As I understand it (through a glass, darkly), you
boot your system some other way, then "restore" the image. It's
all smoke and mirrors to me. I don't trust "booting some other
way," even though the Thinkpad has a system recovery partition on
the main drive (i.e., my SSD). So, am I being a scaredy-cat? Should I
rely on images and just "get over it" re my bafflement at what
the restore process is? Would the end result be not just the return of my
data files but of all my OS settings, including the registry?


A final thought: is the image, like a virtual machine, just one file that
you only need a running computer to activate?


Thanks for the
hand-holding.