From: Daddy on
I understand the value of mirroring in RAID 1 (and RAID 5.) What I don't
understand is how a home user benefits from storing a mirrored copy of
their data right next to the original drive in a computer or NAS.

Your mirrored copy is not going to help you if your computer or NAS
suffers hardware failure or gets stolen.

I can see how RAID 1 (or RAID 5) could benefit a live system where
uptime is essential, say, an airline reservation system, where you don't
want to take the time to restore the system from a backup.

For a home user, however, I thought backups are supposed to be stored
away from the source: on an external drive (that you can move anywhere
or take with you) or on a remote network drive, for example.

Therefore, it seems to me that for your stereotypical home user, like
me, a RAID 1 (and therefore RAID 5) setup offers no real benefit over
traditional backing up.

If anyone agrees or disagrees I'd be interested to hear your opinions.

Daddy
From: Christopher Muto on
the most common hardware failures are disk and powersupply.
this is why raid (redundant array of inexpensive disks) and redundant
powersupplies are found in virtually every server.
it will not prevent all types of failures but statistically will greatly
improve uptime.
your mileage may vary, and it is no substitute for backup.

"Daddy" <daddy(a)invalid.invalid> wrote in message
news:h7jqja$dmj$1(a)news.eternal-september.org...
>I understand the value of mirroring in RAID 1 (and RAID 5.) What I don't
>understand is how a home user benefits from storing a mirrored copy of
>their data right next to the original drive in a computer or NAS.
>
> Your mirrored copy is not going to help you if your computer or NAS
> suffers hardware failure or gets stolen.
>
> I can see how RAID 1 (or RAID 5) could benefit a live system where uptime
> is essential, say, an airline reservation system, where you don't want to
> take the time to restore the system from a backup.
>
> For a home user, however, I thought backups are supposed to be stored away
> from the source: on an external drive (that you can move anywhere or take
> with you) or on a remote network drive, for example.
>
> Therefore, it seems to me that for your stereotypical home user, like me,
> a RAID 1 (and therefore RAID 5) setup offers no real benefit over
> traditional backing up.
>
> If anyone agrees or disagrees I'd be interested to hear your opinions.
>
> Daddy


From: GTS on
You are correct that RAID 1 is not a substitute for regular backups.
Also, in the fact that we use it a great deal on business servers to avoid
downtime in the event of a hard drive failure.

If you're not concerned about downtime, the only advantage in the home
situation is that the RAID 1 provides real time protection against data
loss. In the event one drive fails you, would be protected against data
loss between the time of the last back and the drive failure.

Although almost all the business servers I manage are set up for RAID
mirroring I rarely see it used in the home.
--

"Daddy" <daddy(a)invalid.invalid> wrote in message
news:h7jqja$dmj$1(a)news.eternal-september.org...
>I understand the value of mirroring in RAID 1 (and RAID 5.) What I don't
>understand is how a home user benefits from storing a mirrored copy of
>their data right next to the original drive in a computer or NAS.
>
> Your mirrored copy is not going to help you if your computer or NAS
> suffers hardware failure or gets stolen.
>
> I can see how RAID 1 (or RAID 5) could benefit a live system where uptime
> is essential, say, an airline reservation system, where you don't want to
> take the time to restore the system from a backup.
>
> For a home user, however, I thought backups are supposed to be stored away
> from the source: on an external drive (that you can move anywhere or take
> with you) or on a remote network drive, for example.
>
> Therefore, it seems to me that for your stereotypical home user, like me,
> a RAID 1 (and therefore RAID 5) setup offers no real benefit over
> traditional backing up.
>
> If anyone agrees or disagrees I'd be interested to hear your opinions.
>
> Daddy

From: dg1261 on
Daddy <daddy(a)invalid.invalid> wrote in news:h7jqja$dmj$1(a)news.eternal-
september.org:

> For a home user, however, I thought backups are supposed to be stored
> away from the source: on an external drive (that you can move anywhere
> or take with you) or on a remote network drive, for example.
>
> Therefore, it seems to me that for your stereotypical home user, like
> me, a RAID 1 (and therefore RAID 5) setup offers no real benefit over
> traditional backing up.


First, consider of all the different ways your system and your data is at
risk:

The hard drive could develop unreadable sectors, or the motor bearing
could seize, or a power supply failure could take out the drive motor or
controller board. A virus could wipe out data, or your partition table,
or a bad Windows update or poorly designed app could hang the system, or
slow it down, or leave it unbootable, or lock it up completely. The nut
behind the keyboard could inadvertantly delete the wrong folder, or
overwrite the wrong document, or your brother-in-law could "help" by
fixing your registry for you. Fire or flood could leave your computer a
twisted mess of glass and metal, or some thief could steal your computer
in the middle of the night. And so on and so on.

How many of these risks does RAID1 protect against? Only a few.

Any responsible backup strategy has to be a multifaceted approach, with
considerations for hardware, software, human error, onsite/offsite, etc.
RAID1 covers only a piece of the puzzle.

I wouldn't call RAID1 worthless, but for the typical home user, IMHO the
negatives overshadow the benefits. The benefits are small, and could
alternatively be covered--albeit, less conveniently--by other methods,
such as imaging solutions from Acronis and others. The downsides include
twice the power, twice the heat, twice the noise, twice the drive failure
rate, and twice the cost.

Let's say you spent an extra $200 three years ago for a second HDD to
RAID1 your 250GB HDD. Now one of them fails, and you have to replace it.
How much will that cost? In this age of terabyte drives, you need a
250GB. (You could buy larger, but you'll only get the use of 250GB of
it.) The convenience provided by having RAID1 came at a cost of $200
then plus whatever the replacement HDD cost today. And you still have a
250GB system.

In contrast, if you had a decent backup system--such as data on a
separate partition or HDD and backed up daily, accompanied by periodic OS
images with Acronis, Ghost, Terabyte Image, et al--you could replace a
failed HDD with any size you want and restore from your backups. You
would have saved that $200 back then, and that money today would get you
a couple terabytes instead of just 250GB. It would take a little longer
to be back up and running, but how often do you think you're really going
to have to do this? (And remember, this means on *the same computer*--
once you upgrade to a new computer, the cost/benefit comparison starts
over.)

For those who would argue that RAID1 is more convenient than having to
deal with imaging, etc... those are apples and oranges. Buying RAID so
you can skip imaging is leaving you with incomplete coverage--partially
naked.

A responsible user would have been supplementing RAID with imaging and
offsite backups, so how much more time would a RAID-less solution have
added anyway?

Are the benefits of RAID1 worth all the downsides? IMHO, not for most
home users.




From: Ben Myers on
Daddy wrote:
> I understand the value of mirroring in RAID 1 (and RAID 5.) What I don't
> understand is how a home user benefits from storing a mirrored copy of
> their data right next to the original drive in a computer or NAS.
>
> Your mirrored copy is not going to help you if your computer or NAS
> suffers hardware failure or gets stolen.
>
> I can see how RAID 1 (or RAID 5) could benefit a live system where
> uptime is essential, say, an airline reservation system, where you don't
> want to take the time to restore the system from a backup.
>
> For a home user, however, I thought backups are supposed to be stored
> away from the source: on an external drive (that you can move anywhere
> or take with you) or on a remote network drive, for example.
>
> Therefore, it seems to me that for your stereotypical home user, like
> me, a RAID 1 (and therefore RAID 5) setup offers no real benefit over
> traditional backing up.
>
> If anyone agrees or disagrees I'd be interested to hear your opinions.
>
> Daddy

You're spot on with your analysis, also applicable to small businesses
up to a certain size. An external drive makes a lot of sense. So do
some of the remote backup services, for some. I guess that explains the
popularity of the remote backup, and the growing number of companies
that offer it.

No matter what backup procedure or service one uses, it is always nice
to be able to check it out to see if it actually works for restoring
data. Then, when disaster strikes, getting back to normal is something
of a done deal. (And that explains why I think that tape backup sucks,
always has and always will. Tape is too damned flimsy for me.)

.... Ben Myers