The Big UnRAID thread

Keep general discussion and overviews here.

 

mine works awesome.

unRAID 4.5.3 Pro
Asus M2N-E SLI
AMD Athlon64 X2 6000+
4GB OCZ Platinum PC6400
128MB Albatron GeForce FX5700LE (PCI)
Supermicro AOC-SASLP-MV8 (Marvell 88SE60xx) (8 channel PCIe 4x)
Marvell 88SX7042 (4 channel PCIe 4x)
JMicron 363 (2 channel PCIe 1x)
4GB Sandisk Cruzer
Norco SS 500s
iCute S901
Thermaltake TR2 550W
Hitachi, Seagate, Western Digital HDDs.

DNLA (PS3MediaServer), Torrent (unTorrent/rTorrent), FTP, Samba, everything a home server needs.

 

Whats performance like?

 

write 30-55MB/sec to disk shares (tops out about 40MB with user shares), read as fast as the disks can read.

 

I've been using unRAID since Mid 2007, started off with one server hacked together from old bits I had lying around in some crappy desktop case that would fit about 8 drives. Since that time things have expanded. I have found that for my needs (media storage & system backups), unRAID has been ideal for its incremental expandability. Drives need not be of the same size, so as you need more space, you buy more drives and expand the array, either by adding a new drive or replacing older smaller ones. Performance is more than adequate for the purposes of Media Storage and Backup. 35-40MB/sec write and 80-90+MB/sec read, depending on the drive. Parity sync speed of Server 1 is about 50MB/sec. Server 1's Motherboard or CPU (can't be bothered to find out which) died recently so I just changed over the Motherboard and CPU and after reassigning the drives, all is good again. A relatively painless process.

SERVER 1

unRAID 4.5.1 Pro (Haven't bothered to upgrade to latest yet)
GA-MA785G-UD3H (HPA Off by default in BIOS)
AMD Sempron 140 CPU
4GB Apacer DDR2 PC6200
5 x Sil3132 2 port PCI-E sata cards (for 10 Extra Ports)
1 x Sil3114 4 port PCI card
3 x Norco SS500s 5 in 3 enclosures
1 x IStar 3 in 2 enclosure
CoolerMaster Stacker 810 Case
Corsair HX 750W
15 hard drives from 500GB to 2TB, mixture of WD & Samsung


SERVER 2 (Where most of the older smaller drives go, maybe they should go to Ebay)

unRAID 4.5.1 Pro
GA-EP35-DS3R
Some Dual Core Socket 775 Celeron
1GB Generic DDR2 RAM
S3 Virge PCI Video card
2 x sil3132 2 port PCI-E sata cards
1 x sil3114 4 port PCI card
3 x Coolermaster 4 in 3 enclosures
iCute Super18 5G1-BB Case (nice cheap case that can hold loads of disks)
Antec Earthwatts 650W
12 hard drives from 300GB to 500GB, mixture of WD & Samsung

 

some questions -

lose the parity disk, you just put a new one in and it rebuilds?
lose a data disk, same thing applies? is this done hotswap? and if I have sata cages, will it show which disk I want to replace via led?

should I spend a bit more on the parity disk?

im a bit iffy on the whole 1 usb stick thing...if that dies, you need to buy another licence.

what hardware is recommened? i want to go lowest power usage possible, an atom is out of the question due to sata ports.

well, seems there are some atom boards with 6 sata and pci-e, so atom is back in the running.

 

everything has to be done while unraid is offline, ither pc shut down or emhttp not running

so yes, if a disk dies, you shut down unraid replace disks, then star ther back up and hit start on the web ui. cheap cages i guess not youd need one with an intelligent backplane if you wanna work out a drive fault, will cost a pretty penny, if they exist. just build in logical order, make it easy to understand which port goes to which caddy. unraid will list serial nubers for disk changes so you cant really get lost anyway.

parity disk is only important in writes, faster this is faster the writes.

usb stick dies, email tom and hell sort you out. its happend a few tgimes and hes very firendly.

anything intel for low power builds. youll find most disk capcity builds use amd bases due to being cheaper to buy for pcie slots.

 

ok, so I shouldnt bother with hotswap cages then, since I have to shut down anyway. how do you know which disk to replace?

 

as mentioned build in logical order.

you do not have to shutdown, you can just kill emhttp and restaqrt it to refresh the disk lis although this way is unsupported.

its linux disks are given hda1/hda2 etc depending on teh disk controller its on, s oyou might have a sda1/2/3 for onboard and then sdb1/2/3 for a add onc ard this is all listed in the web ui and its pretty easy to match number with port number, it also lists serial number of hdd.

 

I use a coolermaster RC590 with 3 of the 4in3 cages. So for me, the 12 drives go like so: parity drive at the top, and then disk 1 through to disk 11 down the line. So if drive 8 is dead, then I know to look in the lowest 4in3 drive cage and grab the top drive. Then I can verify using the serial numbers unRAID provides.

The drive replacement is a bit of a hassle with the coolermaster 4in3 drive cages, but they are cheap and so far I have only had to add drives to my system and not replace any. I don't imagine replacement to happen frequently but it would be nice to have those hotswap backplanes for the convenience.

With mechanical drives having symmetrical read and write performance, a faster parity drive won't make any difference since the other drives will determine the speed anyway. That being said, I'd make sure the parity drive also wasn't the slowest, but between speed and capacity, capacity is more important.

As for the USB boot drive, the whole thing uses about 50MB and gets copied into RAM at boot time, it only ever gets accessed during boot time and when you make changes to your array (e.g. new drives, new shares, new users). This is why it's simple to update the unRAID OS, just copy new files onto the USB share and reboot. The system files aren't in use since they sit in RAM so can easily be overwritten.

As for lowest power draw, I think people have found the sweet spot to be an intel Core i3 setup. Atom is only marginally less and the performance tradeoff is not really worth it (i3 will spend more time in idle than atom).

I would go Core i3 530, G.Skill ECO 1.35V ram and undervolt the system as far as you can go at stock without affecting stability. You should be able to hit about 30watts idle without drives on an efficient PSU. Also, since it is a fileserver, pick a motherboard with just enough features and not too much else that you'll never use since they add to power draw. Intel motherboards are known for low power draw, their featureset being sparse in comparison to say Gigabyte boards.

 

yes, but writing is a 3 step process for the parity drive (as it has to verify the parity data bit is correct), and a one step for the data drive, which is why your parity drive needs to be super quick.

you could always use a cache drive but imo its not worth the sata port.

 

cache drive?

i'll look into the 530 undervolting, so far an atom D510 with enough sata ports+pci-e for sata card runs around $230 (add another 100 for a 8 port card)

12 ports is all I need, as thats all my case supports, and i'll probably just replace drives with larger ones instead of trying to find an extra port for a small drive

 

yeah a temp drive you can write to at full speed and then defer the writing to the protected rray for idle/later
becuase a normal hdd will write at 60MB+ whereas calculating parity will slow it down but about half so you can delay it. this means you will have data thats not protected, this of course isnt worth it for me

 

ah ok, well my current server is at .01% utilization per day, so I guess I probably dont need a cache. i'll only ever pull 10mb/s from it anyway (the odd movie)

if a 2tb drive dies, how long is a rebuild usually? i'd feel better if there was a dual parity disk but im not sure if thats possible.

 

teh rebuild is as fast as the hdd can write, so about 5-6 hours for a 2tb i think.

 

There are plans for a dual parity solution, as well as spanning the parity drive across multiple smaller drives. They've been in the works a while, but are low priority and so we haven't seen it yet.

Also, while most parity calcs shouldn't be processor constrained, I believe some users with Atom systems do report slower speeds, mostly due to the ICH not being up to snuff as compared to the higher power parts.

 

It just happens that the remaining parts I've been waiting for (A+ to umart VIC), for my first UnRaid build has arrived.

Specs:

• CM Stacker 810 (E-ATX, ATX, m-ATX, BTX, m-BTX) 810 (existing, has been collecting dust)
• Corsair VX-450 ATX 450W Power Supply 120mm fan
• Supermicro C2SEE MBD-C2SEE
• 2x OCZ 2G DDR3 800 PC3 6400MHz Gold Series
• Intel Celeron Dual Core E3300 2.5GHZ 800FSB LGA775
• 2TB WD20EARS - Parity Drive
• 1x 2TB WD20EARS
• 2x 1TB WD
• 2x 500GB WD

I know what I'm doing this weekend!

 

can you build unraid without losing existing data ?

 

AFAIK you have to have UnRaid format any drives installed prior to adding it into the array. I took the opportunity to grab an extra 2TB drive and use that initially while I slowly offload current data from my PC to the array and also move the existing drives accross as data is moved. There are guides here in moving existing data:

http://lime-technology.com/wiki/ind...f_my_existing_data_to_my_new_unRAID_server.3F

 

What is the main benefit on running un-raid? i have googled, but to my understanding:

Largest disk = parity
add what ever other disks you like?

Is there any clear benefit? is it better than a raid5 or 6 setup? specific file systems used on this? easily expandable?

Building a new File Server myself, trying to make a decision on what to do!

using Un-raid, is it simple enough to add things to the OS, eg. torrent or newsgroup client etc?