I am planning to build a network attached storage server (just for my
LAN, NOT accessable from outside), but I'm not totally sure how to go
about it. Here are my goals:

* One giant volume where everything can be stored in folders. (and
therefore easy to rearrange. moving stuff is a pain when it has to
copy from one drive to another)
* Did I mention giant? Probably eventually I'll want over 1 terabyte.
(home videos are big)
* Redundancy. I don't want to lose anything in the case of a drive
failure, and don't want to worry about "bit rot" on dvds. (home videos
are irreplaceable)
* Speed is NOT a consideration. This is meant to be long term storage.
I won't be editing the videos over the (100mbit) network, I just want
to play them from time to time (which should be fine over the network,
right?).
* Remote administration/monitoring, email alerts (or an alert message
on the remote machine) in case of a problem. (I intend to tuck this
away in an unused room, so beeping from the pc speaker might not catch
my intention)

So I'm thinking 8-channel SATA RAID is the way to go. 6 200gb drives
in RAID 5 will get me around 1 terabyte, as I understand it (5 drives
* 200gb. 1 drive for parity). This would leave 400gb of headroom if it
allows me to add more drives later ("online capacity expansion" I
think will make this possible). I want to make the whole thing a
single network share using Windows XP Pro, since that is what I'm
familiar with and I'll know how to set that up. Windows will be
installed on a separate little old drive so there's no clutter on my
storage array.

Here's what I know, and what I think I know. I'm looking for
confirmations and corrections:

[PCI]
The 8-channel SATA RAID cards I see are 64 bit PCI-X (or PCI Express?
I'm actually a little confused by the different names and versions.. I
think most home desktop systems have PCI 1 and the 64 bit ones are PCI
2.2. I think.). I read somewhere that these cards will function on a
32bit, 33.33MHz PCI bus (like I have), albeit much slower (but like I
said, speed is not an issue for me). If this is correct, I'll be able
to use one of my old computers.

[Future Expansion]
I was hoping to get a cheap controller, such as the HighPoint
RocketRAID 1820, but it doesn't seem to support online capacity
expansion, which means I won't be able to add a drive to my array
later if I need more space, right? But I'm also thinking that if the
price difference between this controller ($200 USD) and some of those
that do support online capacity expansion ($500+) is equal to the
price of a few more drives, I might as well get all 8 at once, with
the cheaper controller, instead of 5 or 6 drives now with the
potential for more later. So maybe that isn't such an important
feature for me, even though it sounds handy. BUT maybe online capacity
expansion only refers to expansion without bringing down the system?
If it's possible to add drives later, I don't care if I have to
restart it and have it offline for a few hours while it does its
thing. Some clarification here would be appreciated.

[Spare Drive]
A hot spare is an unused and inactive drive in the array that is
powered up when another drive in the array fails, and the data that
was on the failed drive is reconstructed onto the spare, so the amount
of time your data spends without redundancy is kept to a minimum. But
if I don't use a spare drive like this, and one fails, I will be fine
as long as I replace the bad drive before a second drive fails, right?

[Windows File Sharing]
Will the other machines on the network (Windows XP Home and Pro
systems) be able to access the full terabyte in the shared folder?

[Hardware Upgrades]
If I get this all set up and going in one (old) computer, and my (old)
motherboard (or any other hardware) kicks the bucket, can I transplant
the whole controller+disks into another machine?

This will be a decent-sized investment, so I want to make sure I don't
get the wrong stuff. Mainly I'm looking for either confirmation of my
plans (which currently are to get the HighPoint RocketRAID 1820 plus 8
200gb SATA hard drives (or only 4 at first, if I can add more later),
and stick them together in an old 650MHz Duron machine with a 100
base-tx network card... hmm, and a new case too I guess), or
corrections of my assumptions, plus any informed suggestions about the
way I'm going about this in general.

Thanks in advance! (heh, and thanks for just reading to the bottom of my post :)

How about these?


http://h18006.www1.hp.com/products/storageworks/nas1200s/index.html

http://h18006.www1.hp.com/products/storageworks/nas2000s/index.html

Wow, long question. I'll answer a couple of parts:

Spare drive: If you have no hot spare and a drive fails your data is
fine as long as no other drives fail. In your case I doubt a spare
drive is going to be required.

Future Expansion: The capabilities may be there in SATA based RAID
cards, but I'm leary of this feature unless it is in a proven high end
RAID card. If anything goes wrong you could potentially loose your
whole array. Buy all the disks now if you can afford it.

Windows File Sharing: If WIndowsXP will see 1TB of disk space, then
when you create the share all your other networked machines will be
able to use the whole thing.

Hardware upgrades: As long as your RAID information is intact and your
data wasn't corrupted by a pc crashing then you should be able to
transplant the whole array into a new computer. The only issue will be
if your OS is installed on the array, in that case you would have to
deal with the hardware changes, installing new drivers etc. That can
be a pain. Installing the OS on a large RAID5 array isn't really
something I'd recommend anyway. Have an internal drive, or an internal
mirrored array for your OS.

Online expansion is just that, expanding the array set without having
to delete the array and re-create it. Prior to this feature the only
way to increase the size of an array was to back it up, delete it,
recreate it larger and restore the data. Not a fun time.

Backups: Have you thought about having a backup component to this
system? If your data is this important to you I would recommend having
a good backup system instead of an elaborate RAID system (both if you
can afford it). Buy a good LTO version2 tape drive (or small library)
and backup your system on a regular basis. Have a number of tapes that
you reuse on a rotation schedule. I understand the desire to not have
bit-rot etc., but leaving this important data strictly on a PC system,
even one with RAID, is not a good idea. More than one drive can fail
at once, a power hit could bump the system and corrupt the drives or
any number of other issues could destroy the array and your data is
lost. Take some time to think about backups.

forgey

Thanks, forge, for the response.
Your suggestion of tape backups sounds to me like providing redundancy
to data that's living on hard drives ("Have a number of tapes that you
reuse on a rotation schedule."), but this is not possible for me,
since I don't have the hard drive space to store it in the first
place. So far, I've been burning stuff off to dvds to make room on the
hard drives, and I'm not happy with this for 2 reasons:

* The dvd is the only copy, and if something happens to it (scratch,
bit-rot, etc), I'm sol.
* It is inconvenient and time consuming to burn it all, and then to
look for a specific disk when I want to retrieve some data at a later
time.

I suppose I should have included that second point in the original
post. If you meant tapes in addition to a bunch of hard drives, that's
probably more than I want to spend, and I think the RAID 5 will
provide as much security as I can reasonably expect at an affordable
(if I stretch the word enough) price. The computer will also be on a
UPS/surge protector.

I'm not entirely sure what to make of your comment about Windows (xp
pro) file sharing: "If WIndowsXP will see 1TB of disk space, then
[you're fine]." It sounds reasonable enough, but since I don't know if
the first part of that sentence is true (I don't have the TB yet), I
don't if it's meant to be a definitive "yes, you're fine" answer.

Also, still no mention mention of PCI-X/Express, but I have now read
in more than one other place that it should be backwards compatible
with my lowly 32bit PCI bus.

To koldo: sorry, those are much too expensive for me (>$6000) because
they're geared for performance in a professional environment...
Assuming no major problems with my current plan, what I'm asking about
here should only cost around $1500.

<n00b>Am I supposed to do something so forge can get some money? (This
is my first time using Google Answers)</n00b>

Most 66mhz, 64bit PCI cards are compatible with 33mhz, 32bit slots.
They will probably just offer less performance (as you mentioned).
Just ensure that it will fit in a regular PCI slot and will fit in
your case. Some of those 64bit cards are pretty long. A quick call to
whoever manufactured your PC with the model # of the card you are
talking about should give you the answer.

What I was talking about with the tapes was mostly a suggestion to
backup your new RAID array, if you had the money. Tapes and a tape
drive aren't cheap unfortunately, but it sounded like this data was
pretty important to you. If you can't afford that then I'd suggest you
keep burning important movies to DVD to watch regularly and keep your
RAID array for watching online and archiving. Then you've got the data
in two places.

Does WindowsXP support 1TB of disk space? I think so but I couldn't
quickly see any reference to it. Again, a quick call to MS Support
will give you the answer, but you'll need to pay for that. Perhaps a
fine Google Answers researcher has that answer?

As for some way to give me money, don't worry about it :) I'm not a
researcher so I can't be paid. If one of the researchers comes along
and answers the other parts I left out, pay him.

forge

This page: 

http://www.winnetmag.com/Article/ArticleID/27253/27253.html

Seems to suggest that on a WindowsXP drive formatted as NTFSv5 you can
support up to 256TB. I'd say you should be fine.

forge