Mirror

[rob p]

I have two drives in an XP Pro system. The second is only there for backup
in case the main one fails. I just installed and formatted it.

What are some good software programs that will allow me to mirror one to the
other? And are there shortcomings I should be aware of? Is this a continuous
mirroring or does it sync at night? Degregation problems?

This drive would only be used if the first one failed. I would expect it to
be bootable of course.
thanks.

 

[Carey Frisch [MVP]]

BackUp My PC
http://www.stompsoft.com/backupmypc.html?SourceID=afc_cj_backup

--
Carey Frisch
Microsoft MVP
Windows - Shell/User
Microsoft Community Newsgroups
news://msnews.microsoft.com/

-------------------------------------------------------------------------------------------

:

| I have two drives in an XP Pro system. The second is only there for backup
| in case the main one fails. I just installed and formatted it.
|
| What are some good software programs that will allow me to mirror one to the
| other? And are there shortcomings I should be aware of? Is this a continuous
| mirroring or does it sync at night? Degregation problems?
|
| This drive would only be used if the first one failed. I would expect it to
| be bootable of course.
| thanks.

 

[Vanguard \(NPI\)]

I have two drives in an XP Pro system. The second is only there for backup
in case the main one fails. I just installed and formatted it.

What are some good software programs that will allow me to mirror one to
the
other? And are there shortcomings I should be aware of? Is this a
continuous
mirroring or does it sync at night? Degregation problems?

This drive would only be used if the first one failed. I would expect it
to
be bootable of course.

Mirroring requires hardware (or softare) to perform the mirroring (where one
drive is made the duplicate of another). Windows XP includes software
mirroring but I don't think it can include the OS drive. It provides
software RAID (RAID-1 is mirroring). If your hardware supports mirroring,
you use it to mirror a second drive against your first drive. This
mirroring is continuous. When you change a byte on one drive, it gets
changed on the other drive, hence the mirroring.

Backing up to the second drive is NOT mirroring. You are just copying files
over there to provide a fast backup device from which you can restore. You
can save backups to Zip drives, floppies, CD-Rs, DVD-Rs, internal or
external hard drives, or even to USB thumb drives (up to the capacity of the
backup device). All you are doing is saving files on the backup drive. You
are NOT mirroring your drive there.

If you don't have the hardware to mirror your drive, and if the drives to
mirror include the OS drive (which precludes using software RAID included in
Windows), you could use a disk/partition imaging program to save static
image filesets onto the backup drive. This is also another form of backup
where you save files onto the backup drive rather than actually make it
mirror your production drive. Acronis TrueImage, Ghost 9 (which now uses
the DriveImage engine from Powerquest that Symantec bought), and Terabyte's
BootIT NG are some imaging products you could use. They provide compression
and only save the contents of those sectors that are actually inuse (which
means they must be able to read the file system employed within the
partition being imaged). So you can have several images from which you can
restore that are saved on the backup drive. There are some products that
try to be a bit more transparent in saving incremental change data to the
backup drive, like RestoreIT and Goback (provided you use their save
partition on your second drive, since putting it on the same drive means you
lose that data along with your real partition(s) when that drive failes).

If you cannot have dynamic mirroring as noted in the first paragraph using
hardware (or using software RAID if you want to mirror drives other than the
one with the OS), you can create a static mirror by occasionally cloning
your first drive onto the second drive. TrueImage, Ghost, PartitionMagic,
and other such utilities let you clone your hard drive to another one. In
fact, you can download a freebie copy of Western Digital's diagnostics tools
which includes a drive clone function. Here you are creating a static
mirror since the cloning is only performed at the time you ran the program.
Any changes to your hard drive that were made since your last static clone
job would be lost when the drive fails or gets corrupted.

If you want mirroring, you'll need the hardware to make sure it is dynamic
(i.e., mirroring is continuous and immediate so you actually do have a drive
that mirrors the original). If you don't care about losing changes between
when you clone the drive, and because you don't have the hardware for real
mirroring, use a drive cloning program. If you don't have hardware
mirroring and don't want to lose (many) changes since the last manual clone
job, use RestoreIT or GoBack which monitor changes dynamically to allow you
to recover you system to a prior state, schedule TrueImage or another
imaging program to make periodic snapshots of your system (i.e., you can
still lose changes after the last snapshot but have reduced the size of that
loss), or schedule backup software, like Stomp Inc Backup MyPC, to
periodically save copies of your files. Windows XP comes with its own
backup program but it will not compress the saved files when storing the
backups on a hard drive, but Backup MyPC will compress so you can get more
files saved on the backup drive.

 

[John Barnett MVP]

There are a number of imaging applications.

Norton Ghost
Acronis True Image
Casper
BootIT NG

I personally use Powerquest's Drive Image (Now Symantec Ghost). This
application compresses the information during imaging, thus you require less
disk space. As an example my XP Partition is 30GB with 9.5GB of space used.
Drive image reduces this down to around 4.75GB. Other software, such as True
Image and Casper simply copy the whole drive, empty space as well, so with
Casper, for example, my 30GB partition would be created as a 30GB image,
thus saving me no space at all.

--
John Barnett MVP
Associate Expert
http://xphelpandsupport.mvps.org

The information in this post is supplied "as is". No warranty of any kind,
either expressed or implied, is made in relation to the accuracy,
reliability or content of this post. The Author shall not be liable for any
direct, indirect, incidental or consequential damages arising out of the use
of, or inability to use, information or opinions expressed in this post..

 

[Ken Blake]

I have two drives in an XP Pro system. The second is only there for
backup in case the main one fails. I just installed and formatted it.

What are some good software programs that will allow me to mirror one
to the other? And are there shortcomings I should be aware of? Is
this a continuous mirroring or does it sync at night? Degregation
problems?

This drive would only be used if the first one failed. I would expect
it to be bootable of course.

You're talking about backup and mirroring in the same breath, but they are
really two different things. Mirroring (RAID 1) is a technique used in a
situation where downtime can't be tolerated--where the cost of even a few
minutes downtime can put you out of business. Itis continuous and permits
automatic seamless substitution of the mirror drive for the original if the
original should fail.

It's important to realize that mirroring is not a substitute for backup.
Even those business which use mirrors also do regular backups.

Assuming that what you really want to do is not mirroring, but a regular
complete backup of your drive, I urge you to reconsider your backup
strategy. What you are planning is better than no backup at all but just
barely. I don't recommend backup to a second non-removable hard drive
because it leaves you susceptible to simultaneous loss of the original and
backup to many of the most common dangers: severe power glitches, nearby
lightning strikes, virus attacks, even theft of the computer.


In my view, secure backup needs to be on removable media, and not kept in
the computer. For really secure backup (needed, for example, if the life of
your business depends on your data) you should have multiple generations of
backup, and at least one of those generations should be stored off-site.



My computer isn't used for business, but my personal backup scheme uses two
identical removable hard drives, which fit into a sleeve installed in the
computer. I alternate between the two, and use Drive Image to make a
complete copy of the primary drive.

 

[Plato]

I have two drives in an XP Pro system. The second is only there for backup
in case the main one fails. I just installed and formatted it.

What are some good software programs that will allow me to mirror one to the
other? And are there shortcomings I should be aware of? Is this a continuous
mirroring or does it sync at night? Degregation problems?

http://www.centered.com/download/sc2000.exe

 

[dreamtheater_142]

Hi, Rob.
I think you definitely need backup
software[http://www.acronis.com/homecomputing/products/trueimage/] to
make an incremental backup.
In your case it will be the best solution. I tried it by my own PC. So
just create a secured zone on your second drive, create full system
backup, after that you could make an incremental backup every day by
built-in scheduler.
It serves me just wonderful, very easy, fast and comfortable!
Recommend.

 

[Vanguard \(NPI\)]

There are a number of imaging applications.

Norton Ghost
Acronis True Image
Casper
BootIT NG

I personally use Powerquest's Drive Image (Now Symantec Ghost). This
application compresses the information during imaging, thus you require
less disk space. As an example my XP Partition is 30GB with 9.5GB of space
used. Drive image reduces this down to around 4.75GB. Other software, such
as True Image and Casper simply copy the whole drive, empty space as well,
so with Casper, for example, my 30GB partition would be created as a 30GB
image, thus saving me no space at all.

--
John Barnett MVP
Associate Expert
http://xphelpandsupport.mvps.org

The information in this post is supplied "as is". No warranty of any kind,
either expressed or implied, is made in relation to the accuracy,
reliability or content of this post. The Author shall not be liable for
any direct, indirect, incidental or consequential damages arising out of
the use of, or inability to use, information or opinions expressed in this
post..

TrueImage only does a *full* image if the file system is corrupt or it
doesn't support it (i.e., it is an unknown file system). If it does
understand the file system, like FAT/16/32 or NTFS4/5, then it only saves
the sectors that are in use and skips those not in use. I don't know if TI
also incorporates compression where it would reduce the number of saved
bytes but then it would need contiguous bytes and that devolves into doing a
logical backup rather than sector-by-sector imaging. TI will also do a full
sector-by-sector image (for only used sectors to save space) and follow up
with incremental images where only the sectors that have changed since the
full image will get saved, very similar to incremental logical file backups.
Most imaging programs actually only image the specified partition(s). For
example, in DriveImage 2002, you saved images of partitions, not of all
partitions on the disk. TI can also save a *disk* image.

While an imaging program is very nice to provide a snapshot of your drive
(partition or disk) to provide a restore back to that same state, they only
provide static images. That is, the image saved is the one you use to
restore from, and the image is only created when you actually run the
program to save the image. Yes, you can schedule the imaging programs to
save images periodically but that is also like scheduling logical backups to
run periodically. You will still lose all creates or changes since that
last image save. Products like RestoreIT or GoBack will save incremental
revisions of changes as they are made. So you can actually choose which
revision of a file to restore. However, since they are monitoring these
changes dynamically, I suspect there is some impact due to their overhead to
perform that monitoring.

Just be sure to save your images or hidden restore partition on a different
drive. If you save them on the same drive, you get the convenience and
speed of restores until that drive dies, and then you lose your data and
your images.

After using or trialing several imaging products, I'd go with Acronis
TrueImage. BootIT NG is okay and provides some other utility functions but
TI seems to a more potent solution. However, after reviewing RestoreIT
which will also save full images (and onto whatever media you choose), I
might go with it. I can have it save the full image on removable media and
use a hidden partition on a second drive for the much smaller incremental
images which get dynamically updated when files are created or changed (so I
get the smallest granularity for restores instead of going back to the last
static image for a restore).