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Ideas for a Home Grown Network Attached Storage?
Ken asks: "It seems that consumer level
1TB+ NAS boxes
are all the rage
right now. Being a digital packrat, with several computers/entertainment devices on my home network, I am becoming more interested in getting one of these for my home. Unwilling to dish out 1K or more up front, and possessing a little of the DIY spirit, I would like to build my own NAS and am interested in hardware/software ideas. While the small form factor PC cases are attractive, my NAS will dwell in the basement so I am thinking of a cheap/roomy ATX case with lots of power. I think that integrated gigabit Ethernet capabilities and PCI-Express on the motherboard are a must, as well as Serial ATA HDDs, but what processor/RAM? How strong does a computer really need to be to
serve files? What about the OS? Win2K3 server edition? WinXP Pro? Linux?"
"I have been using Red Hat and then Fedora Core since it came out but only in a workstation role, and I have little experience with other flavors. What file system should I use for maximum compatibility? I will need it to work with Windows, Linux and several UPnP devices. I am planning on starting out with two or three HDDs in a RAID 5 config. and I would like to be able to add more HDDs as space is needed without any major changes. Thanks for any ideas."
If you think you can beat a device like the Buffalo TeraStation go for it, you will be rich! It was shown at CES, and goes on sale next month in the USA for $999. Gigabit Ethernet, 4 250GB hard drives (RAID 0, 1 or 5 support), 4 USB ports to attach additional external storage devices, built in print server for sharing a USB printer, blah blah blah. I'm going to buy 2 of them!
Urge to post... fading... fading... RISING!... fading... fading... gone.
You don't. Take a bunch of disks, turn them into RAID5 array. Make a logical volume (LVM on Linux) and add the RAID-array to it. Create a growable device on the LVM and format with a standard gowable FS.
When you get new disks simply create a new RAID5 array and add that to the logical volume and add to your current and grow the FS on it.
You don't want everything on one big RAID0, I lost 200G of data that way. I can say I'll never do that mistake again.
Well, the LBD mailing list archive might be a good place to start, since I specifically mentioned it.
Patch 1
Patch 2
Says Tony:
"Here is an "example" patch to fix some of the LBD issues with various
filesystems (ext3, xfs, reiserfs, afs). Unfortunately it looks like
there are many more LBD problems with the filesystems that I didn't fix,
so I am just calling this an "example" patch that shows some of what
needs to be done, but doesn't fix everything."
He later mentions the only XFS fix is in some debugging code, and it appears to be the cleanest of them.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
A few comments about this
-Get the best-value processor that you can find. You won't need the fastest thing out there, but it's better to have a little more "oomph" than you need. If you end up using an encrypted filesystem at some point, you'll want enough power to decript and keep the network "fed"
-Have a plan for adding a second network interface. Maybe you don't need it now, but once the DIY bug bites, you may find yourself wanting to use the machine as your NAT box or as a wireless access point or something like that.
-Think about noise and power use. Yeah, those WD Raptors are fast, but they're really loud, too, particularly if you buy a pile of them. You might want to think about acoustic material for the inside of the case -- your local car customizing shop can hook you up. You'll also want an "overkill" power supply for the case so that you don't have problems when you add more drives later.
-Think about heat and airflow. At this time of the year, it's easy to ignore (Dear Australia: yes, I know it's summer there now), but during the summer, stuffing the fileserver into the closet might not be such a good idea.
-Consider underclocking. If you do buy a better processor than you need, bump the speed down for now. Less power, less heat, less noise.
-Get a BIOS or hardware-level RAID mirror for your "root" disk. You can use software RAID for the data disks, but you want to be absolutely certain that you can recover the disk with information about the software RAID. The RAID does no good if you don't know how to access it.
-If you use Linux, LVM will become your new best friend.
-Consider buying hard drives that are carried by your nearest Best Buy/CompUSA/other computer store. You don't actually have to buy the initial batch from there, but if a drive in the RAID set goes bad, you'll want to replace it ASAP. It's nice if you can do that tonight rather than "in a few days".
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