Re: RAID array for home


"GSV Three Minds in a Can" <GSV@xxxxxxxxxxxxxxxx> wrote in message
news:spAL49AI+m$GFANd@xxxxxxxxxxxxxxxxxx

Redundancy - So you have the data replicated across 2 (or more) hard
drives, but the whole thing still relies on one RAID controller, CPU,
motherboard, PSU etc. In particular if the controller goes South you may
be stuffed. If one disk fails (which is what you are guarding against)
you
MAY be able to rebuild the array (assuming you can source an identical
disk), but several folks have discovered that isn't so easy either (you
don't find out until it fails, of course).

However, even if you can't rebuild the array, the one working disk still
has
all the data on it, and it is still accessible. So, you still have your
precious data.

As you would if you had just copied it to another place on the network.

Well, if you are going for real time continuous disk shadowing, then you
have pretty much just described RAID1. I'm sold on it since I built a
system, loaded everything on, with dozens of windows updates, and then had
one of the disks fail. That's a day's work that I didn't have to do, because
RAID1 saved my bacon. These days, a lot of mobos have RAID built in, so the
extra cost is just a HDD. Say 50 squid.


And this assumes your controller hasn't copied the cr&pped version to the
second drive too, or that the power spike didn't take out both drives at
the same time.

You still need backups, but it takes a bit of the pressure off IMHO. If I'm
working on a crucial report, perhaps under time pressure, I could easily
have done hundreds of Pounds worth of work since my last backup, and before
you ask I do overnight backups automatically EVERY might. I'm just about to
build myself a new PC (or buy one from Dell), and it will definitely have
RAID1.


You have not made much of a case for RAID - what is the advantage for Joe
Average User?

Joe Average User doesn't have backups that are more recent than last month.
RAID1 will *probably* save his data, depending on what goes wrong. 50 squid
well spent IMHO.


The advantage in the professional world is 'zero downtime' (lose a disk
and keep flying), but in that world we also have redundant PSUs, and
usually multiple systems we can steal motherboards from, or swap drives
into.

We've got more PCs in our house than we have people. :-)


Striping gives some minor speed advantages for people with huge files
(video, for instance), but apart from that I'm pretty unimpressed with
RAID for home users.

--
GSV Three Minds in a Can
9,423 Km walked. 1,827Km PROWs surveyed. 33.2% complete.


.

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