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HOWTO: 0.5TB RAID on a Budget
Compu486 writes "Inventgeek.com has a new how-to article
titled 'The
Poor Mans Raid Array.' The article details how to make a modular .5 terabyte
Raid 5 array for under $250 (USD), and it all runs on the Mandriva flavor of Linux." Drive prices being what they are, this seems cooler than it is practical. Update: 06/25 23:31 GMT by T : If that's not enough storage, Yeechang Lee writes "Let me show off the 2.8TB Linux-powered RAID 5 array I built for home use a few months ago. I provide lots of details on how I did it, what I used, and the results. The Usenet thread has good followup posts from others, too."
this seems cooler than it is practical.
Perfect for slashdot!
The Poor Man's Redundant Array of Inexpensive Disks.
That aside, a decent motherboard will come with a RAID IDE controller, so you could easily just grab a pair of 250 WD caviars. Or go the cheapo route and do maxtor.
Possible new Slashdot Category?
Nothing for you to see here. Please move along.
You can't handle the truth.
I seriously doubt that this is cool nowadays. A huge case, a lot of fans and the heat it generates isn't something in anyway impressive nowadays.
It takes just TWO modern disks to get 1/2 terabyte of space, and not much more ot get them in raid5, plus you can have a compact box (the one in TFA is very boxy and ugly) and a lot less noise and power consumption.
Not impressive. Sorry.
Sparks:Gadget:Beer Maker
Okay, half a terabyte? Hardly worth lifting a finger for. I have more than 2.5 terabytes almost entirely of porn. And not only that, but it's all stored on 20 IDE drives of various sizes, in external USB cases, plugged into three 7-port D-Link USB hubs, plugged into a PC.
That's a lot of storage.
That's balls-to-the-wall.
I'll take a picture of all the drives stacked up on one another on the desk (5 rows, 4 drives tall).
I take my porn seriously.
Only reason it's budget is because they bought drives off eBay . . . personally . . I think I'll skip eBay if I'm buying Drives.
Your hair look like poop, Bob! - Wanker.
That seems like a lot of screwing around.
Why not just hang a four *large* drives in a workstation with MB that does RAID 1+0? Yeah, it'll cost more than 249, but it won't involve a 50 lbs box of drives..
http://request-header.info
This is a bit off-topic, but I want to share my most recent experience with linux-raid
A few months ago, I decided I'd put together a RAID5 system in a dedicated box, to be used as network storage. I put together a Duron 1.6 on an ECS (I know!) K7VTA3, 512mb RAM, a Promise IDE controller, and 4 200GB drives. I figured the kernel-based software raid would be fine for my purposes.
I installed linux to a normal partition, then set up the RAID array. Everything seemed fine. I set up samba/nfs shares and ftp. Files seemed to transfer just fine. But for some reason, if I transfered a large file over the network directly to the RAID, the md5sum would have changed, no matter how I transfered it. To make things even more strange, if I transferred to a non-RAID partition, then directly used mv or cp to place it on the RAID partition, it worked great. Strange.
I never quite figured it out what was wrong, and I scrapped the project, with the intention to try again with some more decent hardware. Any ideas as to what happened?
This project looks like a giant, hot, slow, old-tech, loud, power-hog of a 500 Gig 'drive' for $250 (low-ball estimate with all the eBay pricing and special batch price on the drives the author got, and not counting time/labor).
A 400 Gig drive (probably of equal or better reliability overall and a warranty) costs about $260 on newegg.
Reminds me of people using 486's as routers/firewalls when you can pick up a Linksys or D-Link for $20 or $30.
Thanks, but no thanks.
Imposing Libertarian views on everyone online since 1992.
What's with the .5TB? Is it not more standard to call it 512 GB, which, at least in my opinion, sounds far more impressive than .5 TB?
This is not economical, cutting edge, cool, nor is it practical. Why?
1) The drives are used. If you want to impress us, do it with new components with warranties (even refurb). Used makes it impractical and unreliable, even moreso because you didn't use hot swap.
2) It is only 500GB. This can be achieved in a RAID5 configuration with 3 NEW UNDER WARRANTY 250GB drives.
3) Heat. This negates the whole "cool" (both figurative and literal) label.
4) Power. Old drives suck up alot of power. Putting alot of them in a single case is going to draw a major stupid amount of power. Fewer drives can achieve the same effect with a reduced power draw. Did you take a page out of the AMD and 3dfx design methodolgy when you thought up this project?
Feed the need: Digitaladdiction.net
Nice project but.. at $15 for a 50gb drive 250gb raw will cost you $75. Add in shipping and I bet you are at $100+. I can get a seagate Sata 250Gb from Newegg for 120. I would rather have three of those RAID 5'd for 500Gb useable that some big, loud, hot, power hungry, loud drive array.
After paying for the electricity to power this thing, you would be much better off with a RR1820A and some Sata drives for about $1000. Not only would it use a lot less power, it would give you a lot more storage. The bucks now are not so much in the hardware (8 250 GB drives + a RR1820A $1100 ~ $250 for the size array this guy made), but in powering the beasts and keeping your house cool in summer at the same time. The way I figure it, you get about a 20:1 power saving on an equivalent sata array.
$60 a barrel oil? What $60 a barrel oil? Must be nice not to have to pay your electricity bills...
Spam, of course.
Seriously though, there is way more than 500 gigs of free content (including source code) available on the web. If you've got a DSL connection or faster, you can easily fill up half a terabyte.
This was exciting...3 years ago. I understand that this is on a "budget", but only 500 gb?
Earn a % of cash back from Newegg, Tiger Direct, Walmart.com, and more: http://www.mrrebates.com?refid=458505
- Buy 3 250GB EIDE or SATA HD's very cheaply.
- Plug them into your cheap linux PC (with at least a 400Watt powersupply). If EIDE then make sure each drive is on its own (master) channel. If your BIOS supports "hardware" RAID, disable it.
- Use a low-level drive diagnostic fitness test to burn the drives in so you can be sure they won't fail right away. A great tool for this is The Ultimate Boot CD, as well as the 'badblocks' linux util.
- Assuming your 3 new drives are drives sdb, sdc, and sdd, with your bootdrive on sda (or hda), you should now partition each of them (instead of raiding the entire disk). I recommend creating one primary partition which is slightly smaller than the fullsize of the harddisk, such that if you buy a replacement drive of another brand and it isn't the EXACT same size, you won't be SOL when adding it. Mark the partition type as "FD", which is the raid autodetect type.
- Verify that your kernel supports software RAID by checking that
/proc/mdstat exists, or by checking for the multidisk "md" module in the output of "lsmod | grep md" after attempting to "modprobe md" and "modprobe raid5". If not supported, then... figure that out yourself.
- Now the fun part (assuming mdadm's installed):
/dev/md0 --level=5 --raid-devices=3 /dev/sdb1 /dev/sdc1 /dev/sdd1 /proc/mdstat
- Put a filesystem on the md0 device with mke2fs
/dev/md0 (or mkreiserfs, or whatever)
- Add a line to your
/etc/fstab to automount your new raid array at /raid5 or wherever.
- Oh, and if your distro doesn't automatically detect your array on reboot, you need to fix that by putting this in your init scripts somewhere:
Now, wasn't that easy?mdadm --create
View the status of the raidset construction by cat'ing
mdadm --assemble --scan
Power to the Peaceful
1. Get a big server tower case w/5+ 5.25" bays.
.7TB to boot. Or get a PCI EIDE raid card compatible with both Linux and Windows and go to town with RAID-0 and 1TB.
2. Get 4 250GB EIDE drives (cheap anymore!)
3. Get 4 $20.00 CompUSA lockable EIDE drive trays.
4. Get an SMP board + CPUs and slap 'em in there.
Ta-da. One power supply, four quiet drives, one case, software RAID-5 easily swappable with 2 dedicated fans per drive, looks professional, comparatively quiet, with the benefit of included scalable SMP workstation. And
There was a time when a SCSI array of many, many drives in a separate case at 10k RPM was something to lust after at home, but these days it just isn't. You can get close enough at home while saving space, using less power, and getting better overall performance.
STOP . AMERICA . NOW
I just recently built a file server for my home. The most important considerations for me were data protection (I've got too much to lose), reliability, economy of operation and quietness, since the server would be in my office running 24/7.
.. NO.
.iso to/from it at more than 40mb a second. It's protected and will safely shutdown in an extended power outage.
First off, Low-noise is my new religion (with 8 PC's in my office, it makes a huge difference), and secondly I don't belive in skimping... being frugal and practical yes, but cutting quality to save a buck (a la walmart)
So to achive that I acquired the following:
- Antec Sonata Lifestyle case.
- nForce 2 motherboard with out chipset cooling fan (just heat sink)
- ATI Radeon 9200se video card with out cooling fan (just heat sink)
- Mobile Athlon XP 2400+ CPU - 35 watts
- 22 db Socket A Heat sink/Cooling fan unit
- 22 db 12cm fan.
- Gigabit NIC
- 512mb RAM
- Combo optical drive
- Samsung 120gb drive (to hold OS, and work space)
- 3ware Escalade 7504-LP RAID controller
- 4x Maxtor 300gb 5400 RPM Drives (chosen for lower heat output over 7200 RPM) drives
- APC 1000va UPS
So put it all together and you get a system that has a total of only 4 fans in it including the one in the power supply. It is the quietist PC I have. The case has a nice rack to hold the 4 RAID drives with cushions to reduce vibration/noise and mount a 12cm fan draw air directly across them, as well as another at the back to produce decent airflow despite their lower cfm ratings.
It runs cool and very quiet. I can't hear *anything* out of that system if my ears are more than a foot away from it. I can transfer large files like
It wasn't $250, but it's good enough for me to do real production work on and sleep better at night.
So I may not have the fastest possible server, but it's still more than enough
You could replicate using 400gb drives for 1.2TB of storage by trading off for the slightly higher heat of 7200 RPM.
I spend my entire life managing large SANs, so RAID is done in the array (EMC, HDS) while basic volume management is done on the host (LVM, VXVM)... so when i first read this I thought that somebody had used linux and a fibrechannel HBA running in target mode (http://www.emulex.com/ts/docfc/linux/430l/target_ mode_intro.htm)
/. and you'll have something b/c you'll have shown something more than 'look what linux can do' that the other OS's have had for years...
Put that up on
And then going on to mount those luns on another system (say a solaris, aix or another linux box). Instead, I was dissapointed to find out that you took a linux box and created enough software RAID to for a TB or more. If this was done with windows, it would be rejected... so why doing it with Linux make it front page news?
I'm surprised that nobody has mentioned the Linux Logical Volume Manager subsystem. It has many of the features of RAID arrays [such as spanning across multiple drives] with the added flexibility of being able to dynamically add [and theoretically remove] drives.
Unfortunately, aside from RAID'ing the volumes or something similar, I haven't been able to find any information on making the system redundant.
Read about it more on TLDP. It's a very robust system that works well on both servers and desktops.
Try: Comparison of nine Serial ATA RAID 5 adapters
I think it would be more interesting to consider a redundent array of independent flash cards. Since it is clear that solid state drives will soon be included in PCs and laptops in the near future it would be nice to address the speed and reliability issues associated with them. This would also help with the heat and all.
Just a thought.
All your attention are belong to my old internet meme.
1) Free -- Machine was an old K6-2 500 (192MB RAM, 1.4G Boot Drive) that I had laying around.
2) Free -- I got a full tower case from my brother in law (no faceplate).
3) Free -- I had a few 120mm fans laying around which I have cooling the drives.
4) $1040 -- 8 Maxtor 250 GB PATA HDs. (8MB cache, 7200 RPM)
5) $215 -- 3Ware 7810 (8 port PATA hardware RAID 5 card).
6) $140 -- APC RS 1500 battery backup. (You don't want the array to suddenly lose power for any reason!)
Total Cost $1395.
What it got me: I have 1400 GB usable redundant storage with a hot-spare. If a drive fails at 1:00am the computer will automatically start the rebuild on the spare drive, and likewise if I'm not home. This was more important than the additional storage. I also know that I can get 40 minutes of power out of the APC if the power goes out. The machine is set up to shut itself down in the event that the battery runs low.
I didn't have to fight with any software configs. The driver is included in the Linux kernel source, and can be compiled into the kernel. I don't have to worry about figuring out SMART data. "tw-cli info c0" gives me easily readable output on all of the drives plugged into the RAID card. It's simple, does the job, is stable as all hell, and was fairly cheap. It would have cost nearly as much to have bought 4 PATA cards (ones not using the flawed silicon image controller) as it cost for the 3ware card off of eBay.
More information here.