Is 15TB RAID5 with different controllers possible?

[AlExAkE]

I would like to build new htpc/server for myself, and I'm going to use Zotac H67ITX-C-E or Zotac Z68ITX-B-E motherboard with Lian Li PC-Q08B case. The case itself has space for 6 3.5" hard drives, 1 2.5" hdd, and 1 5.25" cd/dvd/blu-ray ROM. Therefor I would need 8 SATA ports available, 1 for DVD, 1 for 2.5" HDD with OS (Windows Home Sever 2011 or Windows 7 Ultimate), and 6 ports to put 3TB HDD on each, for 15TB RAID5 array. Both of those motherboard have 2 6Gbps SATA III ports, and and 2 or 4 3Gbps SATA II ports.

My question is, they probably use a different controllers for the different ports, but does that matter? Can I put a HDD on a SATA III port on Marvel controller and 1 HDD on SATA II port on Intel and make RAID with it? In addition, since the ports are not enough, I will buy RAID controller like this one: MODEL# IXBAY-PX237

http://cgi.ebay.com/PCI-E-SATA-x-5-...389?pt=LH_DefaultDomain_0&hash=item5d2e258915

Would that work? Or for RAID I need all the ports to be from 1 controller? Keep in mind, all of the controllers support RAID5. This controller here has only 5 internal, and 1 external port, so I cant use it alone to connect 6HDD on it. Can I use the 5 from here, and 1 from the motherboard, to connect 6 3TB hard drives, to create my 15TB RAID5 array? IF not, please give me some solution. Thanks

 

[Rifter]

with windows home server you are going to want to use the folder duplication(or whatever its called) not raid 5.

Windows 7 i believe doesnt have software raid 5 so thats not an option, as i doubt the controllers software raid will allow arrays across different controllers.

Running linux you would definatly be able to create a raid 5 array across as many controllers as you wanted.

 

[themillak]

also something to keep in mind is that 15TB is over the magic 10 TB likely-rebuild-failure line for a RAID 5 and that you'd be better off with a raid 6

 

[AlExAkE]

with windows home server you are going to want to use the folder duplication(or whatever its called) not raid 5.

Windows 7 i believe doesnt have software raid 5 so thats not an option, as i doubt the controllers software raid will allow arrays across different controllers.

Running linux you would definatly be able to create a raid 5 array across as many controllers as you wanted.

I want to do a hardware raid, not software. From what I know I believe it is the better way to go. AS far as software raid, I've never done one, and I dont know if you can use 2 different controllers in the array aether...

 

[AlExAkE]

also something to keep in mind is that 15TB is over the magic 10 TB likely-rebuild-failure line for a RAID 5 and that you'd be better off with a raid 6

Hmm interesting, I've never heard of that 10TB magic rule... are you sure? How does RAID6 works and is different than RAID5. I want to have as much possible storage with as much security for my data. Thanks

 

[ViviTheMage]

I would not get that raid card ... it's like trusting a Taiwanese hooker with your crack, you'll never see it again when it's gone.

If it's within your budget, get a real 3ware/lsi raid card.

You also can't really raid with drives connected to a raid card, and the mobo...you can only raid with either all drives on the mobo, or all drives on the raid card. I'd put all HDD's on the raid card though, and raid from there. I agree though 10TB is the magically limit for raid5, go raid 6, or raid 5 + hot spare.

Also, back this data up if it's important, and your only copy.

EDIT :

Raid5 leaves you with the ability to lose one HDD, and still work, Raid6 lets you lose 2 drives and still work.

http://en.wikipedia.org/wiki/Standard_RAID_levels#RAID_6


Real raid card :

http://cgi.ebay.com/3ware-9650SE-8LPML-PCI-Express-SATA-II-Controller-Card-/220791997762

otherwise a guy on AT is selling one for $240 :

http://forums.anandtech.com/showthread.php?t=2144339&highlight=9650se

 

[dac7nco]

I would not get that raid card ... it's like trusting a Taiwanese hooker with your crack, you'll never see it again when it's gone.

Ugh, we should really have a RAID sticky in this sub-forum that starts with "If you have to ask...".

OP, what you want to do isn't desirable or feasible in the long term. Using five discs for storage AND playback would spin all five drives whenever you play a video. With disc capacities ballooning, RAID-5 should be removed from the Lexicon.

Just use seperate discs for backup, which only spin-up when you're dumping data to them, and use a single disc for your "current playlists". It's also a great idea to make backups of your backups of your backups of your backups.

A cheap LSI RAID-6 controller with a BBU, two four-disc backplanes, eight 3TB Hitachi discs and SFF-8087 cables will cost you $1,870. If you just want a single large storage pool, go with RAID-10 from your motherboard, and eat the 50% loss in capacity... with 3TB discs, you'll still have 6TB unformatted, which is still a lot, and is in another league of secutiry compared to RAID-5.

Daimon

P.S.: That was indeed a horrible card; actual RAID controllers don't use SATA ports.

 

[Nothinman]

I want to do a hardware raid, not software. From what I know I believe it is the better way to go. AS far as software raid, I've never done one, and I dont know if you can use 2 different controllers in the array aether...

Software RAID is completely hardware independent so you can create arrays out of any kind of disk you can find, at least on Linux. And because it's not tied to any hardware you have a lot more flexibility and control. I can move an array from one Linux machine into another and it'll magically be found and assembled on bootup regardless of how I have the drives hooked up. For home use I don't see any reason to pay for a hardware controller, the restrictions aren't worth it.

 

[ViviTheMage]

Software RAID is completely hardware independent so you can create arrays out of any kind of disk you can find, at least on Linux. And because it's not tied to any hardware you have a lot more flexibility and control. I can move an array from one Linux machine into another and it'll magically be found and assembled on bootup regardless of how I have the drives hooked up. For home use I don't see any reason to pay for a hardware controller, the restrictions aren't worth it.

Exactly, use the onboard SATA and software raid 10 it. Do not raid 5 on software.

 

[Emulex]

i have a bunch of cheap BRI10i (opensolaris folks love this) for sale in fs/t - cheap - 8 devices each so with all 4 you could have 32 drives - 15gb easily do-able with 1 controller and big drives.

 

[aigomorla]

lol OP i was in a simular boat as you were.

I went though a couple of cheap raid cards and everyone warned me on it.

If your going to Raid in that big of a capacity, get a real raid card.
And get one with a decent amount of cache ram.

Also you'll find better controller cards under SAS.
SAS is backwards compatable to SATA, but SAS controllers may require expensive cabling to connect... example.. the SAS Fanout 8087 harnesses are pricey as faq.

But after listening to a lot of my friends... if ur going to raid that large of a capacity, get a beefy controller.

 

[ViviTheMage]

SAS fan out cables are what ... $20-$25? They're not TOO bad. 3WARE makes a bunch on newegg.

 

[Emulex]

yah i got some BR10i controllers (LSI ibm branded) with fanout for $50 (1 card+ 2 fanout = 8 drives sas or sata) - was going to do a big ZFS raid but money got tight. got 4 sets mang. these are REAL raid controllers - just as unreal price lol.

 

[ViviTheMage]

What are these BR10i rebrands of?

 

[greenhawk]

I want to do a hardware raid, not software. From what I know I believe it is the better way to go. AS far as software raid, I've never done one, and I dont know if you can use 2 different controllers in the array aether...

If after hardware raid, then the motherboard options are out as that is not hardware. it is closer to software raid with a few extra bits.

Raiding over multiple controllers means a software raid is needed. That or a good mid ranged or better hardware card that supports multiple controllers in a single raid array.

 

[greenhawk]

Hmm interesting, I've never heard of that 10TB magic rule... are you sure? How does RAID6 works and is different than RAID5. I want to have as much possible storage with as much security for my data. Thanks

The 10TB is more of a rule of thumb IIRC. Personally I use the number of drives per array limit of 5 or 6. The reason begind it is when a drive dies, the chance of a second drive dieing while re-building it is high.

ie: if one byte of data was coruped per "x" bytes read, then if "x" is close to the size of the array, then chance says it will occur.

ie: if "x" is 10 times the size of your raid array, then you have a 1 in 10 chance of loosing all your data during a re-build.

Lots of numbers involved, but as in all things, raid is not a backup.

If wanting protection for large amounts of data, raid 6 is needed (loose 2 drives to parity), but the number of controllers that support it is less, espically at the lower/cheaper end of the market.

For best data protection though, you would be just looking at raid 1 with as many drives as you can use with several backups.

it is all a trade off in the end though. how much do you want to spend and how much are you willing to risk.

 

[Emulex]

What are these BR10i rebrands of?

BR10i are just the magic unicorn lsi that all opensolaris ZFS freaks love. you flash them back to LSI mode and they can be JBOD or RAID - the ZFS folks want them for JBOD since they are doing ZFS raid and you have a VERY FAST very cheap LSI raid controller for 8 drives on the cheap!

 

[aigomorla]

For best data protection though, you would be just looking at raid 1 with as many drives as you can use with several backups.

it is all a trade off in the end though. how much do you want to spend and how much are you willing to risk.

wait.. raid 1 gives u only half the space span'd on all the drives.

If your using more then 5 drives, and u want more then 1 backup, id say go raid6 instead of raid5.

That way u can have 2 fail b4 u lose everything.

But whats more important then what raid u use, is the DRIVE from what im reading.

TLER nonsense, and head parking will lead a dedicated controller to think the drive barf'd and will screw your raid.

So instead of asking is 15TB possible, you should first find out what drives you need and how much the drives will cost to setup a reliable array like that.

What amazes me is people setup large arrays on Raid0, or JBOD with no fault protection thinking its okey.

The moment they realize something is wrong... they have so much storage on the fault logical drive, its impossible to backup.

This is why when u start an array of that size, you need to make sure its reliable at start, or your just slowly digging away at your grave.

 

[greenhawk]

wait.. raid 1 gives u only half the space span'd on all the drives.

true, but if someone wants online data as reliable as possible, raiding several drives into raid 1 (ie: only the space off one drive), then you need to loose ALL the drives to loose any data.

though as will any raid, a virus or someone pressing "delete" will do a better job of data loose than worring too much about the HDD setup.

 

[aigomorla]

though as will any raid, a virus or someone pressing "delete" will do a better job of data loose than worring too much about the HDD setup.

No i used to be old fashion'd like you until i did some research.

This is why research is very important on anything u buy:

http://forums.anandtech.com/showpost.php?p=31802102&postcount=15

Basically TLER on the new drives, or whatever the manufactor calls it, leads to dedicated controllers failing, thinking a working functional drive is actually bad, and it will drop the drive from the array.

Once again.. if u want to risk 15TB of data... hell im struggling trying to setup a 8TB Raid5 array.... and u dont use the correct drives... your digging yourself a very deep grave.