> I am not sure what this philosophical discussion is about.
>
> Some people may not be able to do hourly backups and may not be able to
> tolerate losing all changes since last night's backup. Storing data on raid
> does not protect the data in an absolute sense, but doubles your chances to
> survive a very common hardware failure even on a simple raid 1 - at a *very*
> cheap price.

with software RAID 1 - true. but "doubling the chance" is way too much.

i'm not against using RAID1,10,5 at all, just against thinking of it as 
magic way to protect data which is very very common.

> Your milage may vary, but at work we we have *all* workstations equipped
> with raid for the main data partition - after we lost 4 or 5 days within
> one year by dying hard disks. Even if we calculate this at the internal
> costs only, we could probably buy 20 - 30 SATA Raptors (maybe more, didn't

Raptors are not so cheap.

> check the latest prices).


after you lose some months of work worth data after two disk would be 
overwriten because of say - memory failure, or damaged by virus (on 
windoze) or simply by root's mistake doing rm -rf / , then you will 
replace each raptor by good DVD recorder (cheaper than SATA drive) and a 
bit of DVD+RW discs to copy your work.

i'm sure your work files (not whole disk, but files that are true product 
of your work, and can't be rebuilt) will fit on few (if not one) DVD disc.

Doing differential backup every day will take 10-20 minutes, and (at 
least in NetBSD) can be made while working.

> So, I know you said "raid is overrated" but your arguments sounded like
> you would like to say "let's forget about raid".

probably but even reading YOUR mail i see how much it is overrated by 
people including YOU.

buying extra drive made things a little bit better, but general lack of 
habit of backups is very very bad.

somehow generalized backup policy in your company won't cost more than 30 
Raptors, i'm sure it will actually cost less.

why people don't save their work on NFS/SMB server somewhere? and use 
local drives only for processing, OS and software that can be reinstalled?

then just make sure that this one machine is backed up.




assuming your statement

"Storing data on raid does not protect the data in an absolute sense, 
but doubles your chances to survive a very common hardware failure"


you may do your backups every two days instead of every day having extra 
drive.


did you ever imagine case of fire, or thiefs? both drives will be lost, 
and your company may fall.

Not because of money needed to buy new computers, which is not that high, 
but because of loss of all work.


Once more - i don't say that RAID is bad. i just say that there are very 
few cases it make real sense for security.

anyway - it makes a lot of sense for increasing performance.