Anna said:
Anna responds...
I really can't see why "there is an opposite side to the coin". The whole
idea of what we are discussing is a mechanism that backs up one's current
system, and does it simply, conveniently, effectively, with reasonable
speed, and is reasonably cost-effective. To indicate that this recommended
mechanism is somewhat deficient because it will not be as simple,
convenient, effective, etc. to restore *another* system introduces a
completely different objective, does it not?
No. Every system must include both functions: backup and restore. If
you can back up everything, but you cannot restore it again, the
backup is useless. While it is true that a backup of everything might
help if you want to _restore_ everything unconditionally, if you have
a need to only selectively restore certain data, being constrained to
restore everything is as bad as not being able to restore anything at
all.
For example, if your computer fails, and you are forced to buy new
hardware that doesn't precisely match the old, you must be able to
selectively restore data from the old computer so that all
hardware-independent information is restored, but hardware-dependent
information is not. That way you can configure the new hardware and
then overlay it with all other restored data without corrupting your
new hardware configuration. If you simply restore the Windows
registry wholesale, you restore all the software _and_ hardware
configuration data, blasting the new configuration for the machine and
potentially making the machine unusable.
Anyway, should the user
completely revamp his/her hardware, programs, etc. etc., wouldn't the user
simply make a clone of his/her new system along the lines I've described?
A clone works if you will always restore to identical hardware. But
since hardware changes daily, the chances of being able to restore to
identical hardware after a system has been running for several years
are very slim. You therefore need the ability to selectively restore.
Being able to selectively back up data isn't that big a deal, its only
advantage being that you can reduce the size of your backups that way.
But being able to restore selectively is extremely important. You may
wish to only restore certain files or directories, or you may wish to
restore only certain branches of the registry.
It is the absence of any awareness of the uniqueness of the registry
in most backup software that makes the registry such a pain to deal
with. How many backup products can selectively restore only certain
branches in a registry tree? Indeed, how would you even determine
which branches to restore, and which to leave alone?
Why would a user even attempt to use his/her "old" clone to restore to a
different system?
The old system may have failed, and he may have been forced to replace
it with new and significantly different hardware. But he still needs
all the old data and functionality.
Please refer to my remarks above. A clone is a clone is a clone. Obviously
it's designed to be a clone of the system one has cloned from. If the user
subsequently builds a completely new system then he or she will clone the
contents of that new system to another clone would he not?
If he can. But to do that, he has to build an identical system with
identical hardware. If the hardware is not identical, simply
restoring an entire drive from a clone will probably not work.
Honestly, isn't that what we're *really* talking about?
Sometimes. But the computer world changes quickly, and unless you buy
several identical systems and put all but one in storage, there's no
guarantee that you'll ever be able to restore to an identical hardware
platform. By the time one system fails in a way that requires
replacement, there will be no identical replacements available. The
original clone will have to be restored to hardware different from
that on which it originally ran.
For the overwhelming number of users the basic issue is backing
up one's current system.
But backing things up implies being able to restore them. If you
can't do the latter, the former is a waste of time.
Even large companies make this mistake: they back up everything
religiously, but they have no idea how to restore any of what they
back up, because they've never tried. When the real disaster hits,
they find that they can't restore anything in a way that allows them
to build a usable system. Sometimes they can get around it, in time,
sometimes they are stuck.
In Windows, by far the most likely culprit for this type of problem is
the registry, which has to be selectively restored if the hardware
changes. And unfortunately there is very little discipline in the
structure of the registry, so it may be impossible to figure out what
must be restored and what must be left in its "virgin" state on the
new machine.
It nearly goes without saying that when a user clones his/her drive, he/she
must ensure that the drive is malware-free and suffers no system files
corruption.
How does one do that? For that, you need a trusted system that can
analyze the system at risk. If you are analyzing the system at risk
from _within_ that very system, you may not be able to detect all
corruption. Some malware is very good at hiding itself.
If you clone garbage, garbage is what you'll get. Presumably the
cloned drive is virus-free, so that if the working drive subsquently becomes
virus infected, restoring it from that "good" clone represents one of the
basic advantages of the disk cloning process.
A better practice might be to replace the working drive with the
cloned drive by swapping drives, then put the old working drive on
another machine, wipe it clean, and clone the new working drive back
to it. And this must not be done using any software from the old
working drive, since that might be infected.
It can be a complex problem to resolve.
You're really losing me here. Hopefully, my remarks directly above have
clarified the issue for you.
I've actually had problems like this, in the distant, misty past. The
central problem is that you cannot trust anything that has been
infected, including any OS that resides on the infected device. Since
most PCs have only one OS that _does_ reside on the (only) disk drive,
it isn't completely safe to do anything with them if you want to
eliminate infection entirely. Most malware is not this sophisticated,
but if it is, you have a serious problem.
I'm glad to hear that virus infection is not particularly troubling for you.
But believe me, it is for many, many computer users.
They execute untrustworthy code. They click on attachments, they
download ActiveX components, etc. At some point, they do something
explicit that causes the infection.
Some software can be configured to execute code implicitly, but this
can usually be turned off. I switched from Outlook Express to The Bat
because OE didn't allow me to turn off HTML mail completely, and it's
too easy for executable code to sneak into HTML (even though I turned
everything off in the Restricted Zone and set OE to use this zone).
And it's here that the virus-free cloned drive is especially valuable.
Yes, but you have to keep it away from infected machines when you copy
it back. It would be nice to be able to block all writes to a drive
with a hardware switch for this type of situation. Then there would
be no way to infect a cloned drive at all, period, and anything
restored from it (using trusted software, which is no easy task) would
be clean.
So let's say that the user builds a new machine with different hardware, say
a new motherboard, a new processor, new RAM, new HD, etc. -- in short, a new
system. The cloned drive could *still* be used to re:clone the contents of
the old drive back to the new system.
What about the registry? Some things in the registry are
hardware-dependent, and must not be changed by the restore; other
things are hardware-independent, and must be restored. But these
things are mixed in haphazard fashion in the _same file_. How do you
select what to restore and what not to restore?
Sure, after doing so, the user would
presumably need to install (or reinstall) whatever drivers are necessary for
the new system. But his/her precious programs/data would be intact. And
there's no reason why that newly-cloned drive would not be bootable. There
may be activation issues, of course, assuming we're dealing with Windows XP,
but that's another issue.
The old cloned content may point to software on a drive that no longer
exists, for example. Windows can boot in safe mode with a generic
video driver, so a video driver mismatch is survivable, but other
drivers don't have that protection (as far as I know).
As to "performance" - I take it you're referring to speed of cloning, yes?
No, I mean the speed of the drive (access time, transfer rates). Are
removable drives slower?
Using medium to high-powered processors and modern hard drives, cloning
speed will be somewhere around 1.5 GB/min. Not breakneck speed by any
stretch, but I would guess sufficient for most users. And the nice thing
about the cloning process is that the user need not be in attendance during
most of the process. Once he/she initiates the process, it automatically
performs the cloning process.
This raises another question: since the system is presumably running
and still writing to the working drive, how do you ensure that the
clone is a coherent copy of the working disk?
Some software can take a snapshot of the entire system and use that to
copy the clone, but this requires OS support that isn't always
present. I know the latest version of my FreeBSD UNIX OS does this.
It looks like Windows backup may also be doing something similar, but
I'm not sure. If it isn't done, though, you can get incoherencies in
the clone that may be impossible to resolve. This is especially true
for things like databases, although usually that's more of an issue on
servers than on desktops (on desktops you can often simply stop
processes that are actively modifying disk data).
As to cost, as I mentioned above - about $100 to $150 for the two mobile
racks, the additional HD, and the cloning software.
That doesn't sound too bad.
There shouldn't be a booting problem at all. As I stated above, after the
contents of the cloned drive has been cloned to the new system, it will
probably will be necessary to install a new video card driver in the example
you've given, but there should be no boot problem at all.
What if the driver is something you need just to get the system up and
running? Windows safe mode was invented to deal with this sort of
issue, but unfortunately it's not foolproof (as far as I know).
That's correct. The hard drives are ordinary PATA or SATA drives, nothing
special about them. You just plop them in the tray (caddy), make two simple
connections (power & data cable), and slide the tray into the mobile rack
(which has been installed in the case's 5 1/4" bay, just like a CD-ROM).
Takes about 30 seconds. Obviously you would want the same make/model for the
two mobile racks so that the inner trays would be interchangeable.
So the racks have some sort of sockets that made with the caddies, and
you just bolt in the drive of your choice and thereafter you can plug
and unplug?
That sounds like a cool idea.
I truly hope you seriously consider this hardware configuration.
I'll certainly look into it, as the tape backup situation is getting
more and more out of sync with the real-world requirements of backup
for desktop systems (it still works fine for servers, though, if you
have the money).
Obviously that's a decision you have to make based on your particular
circumstances. As I've indicated above, we're not talking "big bucks" here.
I know, but I'm really poor. I just replaced this desktop because I
had no choice (hardware failure on the old one), and I'm not even sure
how I'm going to pay for that. So every dollar is a problem.
Equipping one's desktop computer with two removable hard drives is not the
"wave of the future", rather, it's here & now.
I'm not so sure. I don't know _anyone_ outside of a few geeks who
does _any_ kind of backup of his or her desktop machine, much less
anyone who is using removable drives to accomplish it.
This, incidentally, is the reason why most digital photos today will
be lost: they are all stored on disk drives that are never backed up,
and once those drives fail, all the photos they contain will go away.
