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I'm not sure I understand what you are planning, but if your plan is to place standard 19" rackmount computer/server cases into electrical patch box - there might be a problem. Those patch boxes are made of thin metal and are designed for much lighter equipment. Simply put - it will not hold the weight of 19" rackmount computer case with all the hardware in it. Besides, patch boxes are typically not deep enough to house rackmount computer cases. When I was building my servers (rackmount Norco 4020 cases), I did consider all kinds of housings, including 19" audio racks, 19" networking racks, electrical patch boxes, etc., etc., I was even considering DYI racks. All because I did not want huge full-height 42-U (about 7 feet high) server rack which are very common and easy to get. I wanted half-height (18-24 U) used server rack, which turned out to be kind of rarity and very hard to find. Along the way I've learned that standard rackmount server cases must be housed in standard server rack, all other options are either unsafe, or ugly, or both. I was almost ready to pay about $900+ for brand new half-height rack, but was lucky to discover used one on craigslist (kinda online flea-market here in USA) for $250... and now I am happy with it.

Added this card to the Wiki.

Good point... I tend to consider cache drive as temporary place for things I (usually) have a backup for, so I'm not afraid of losing it. Now you've got me rethinking my mode of operations...

Mine shows - after a 3TB drive rebuild - 6,605,407 reads on parity and 6,519,764 writes on rebuilt data drive.

Newegg sells (or used to sell) 3TB 7200 Toshiba HDDs for $82 each. Times 4 = $328.

I doubt that. Writing to unRAID means writing to two drives: data drive, and parity drive. Writing speed will be limited by the slowest of the two.

Using RAID 0 is cutting your drive reliability in half (or more). Oh my... I didn't realize that, but your are undeniably right. I'll make a note to myself: it's OK to use RAID-0 for unRAID cache (or anything your are prepared to loose anytime), but don't use it for unRAID parity or any unRAID array drive unless you understand the risk and ready to tolerate it.

You should probably look into those numbers again. Even with your alien craft, are you not going to restore? In doing so you'll perform the massive amount of data transfer to likely encounter the projected 1x10^14 URE. Yeah, restores fail too, especially when you have no regard to the reliability of the drives you are using. I doubt Gary is going to suggest you reduce the reliability of your drives. I'm not suggesting to reduce the reliability of our drives... even if I knew how to do that. What I'm suggesting is that enterprise-grade drives which cost three times the price of desktop greeny, are not worth it in unRAID environment. Failure of the second drive during rebuild falls under category "two-drives failure", and, as I keep repeating after more experienced unraiders - backup is the only real protection against that.

I'm sure garycase will answer, but let me share my thoughts too. I don't really think that the parity reliability matters much. Or that individual data drive reliability matters much. See, in case of catastrophic failure (alien spacecraft crashes into your garage where your server is... was... or your wife decided that your spend way too much time babying the collection and came with an iron cast frying pan to where your server is.. was...) your are losing data no matter how reliable your parity is... was. In case of "normal" single drive failure - so what? That's the beauty of unRAID - shut down, replace the drive, rebuild, move on. Some people keep spare drive ready for this purpose - I used to do this, too. Not anymore. We are still in the Moore's law domain, maybe closing to the end of it, but still in. So - don't buy anything electronic "for future use". When and if a drive fails - go to nearest brick-n-mortar, pay extra fifty bucks for retail purchase with no discount, but have it immediately. It will probably still be cheaper than the spare you've bought a year ago. Real danger is two drives fail at the same time. Well, realistically estimating the probability of this, I tend to avoid "batch-buying" (purchasing multiple drives at the same time from the same vendor), and that's about all that can be done about it. Of course, higher reliability of parity (or any other) drive improves your chances against "two-drives failure", but only slightly. Very slightly. Don't forget that MTBF hours is highly statistical number by itself. Real protection is backup, and backup only.

Lookie here

RAID 0 parity? I guess you are not on the list asking for an additional parity drive (ala RAID-DP). I'm talking about Hardware-Raid setup that some unRAID Moderators seem to be using. Even with that sort of a RAID setup for the parity drive, you'd still benefit from a second parity scheme/drive. Not only moderators...

Is there an ideal car? As one of the most knowledgeable unraiders recently put it - there is no ideal card, but there are two leaders I personally am very happy with my Supermicro cards.

The only thing(s) I can see missing are the SATA cables... and the drives themselves, of course. You will need a SATA card after adding first 6 drives, but that surely wouldn't be a problem with this motherboard. Other than that the build looks very solid to me. Even if your are going to Plex-transcode multiple streams. Some might say that the PSU is a little bit overkill, but not me. Not for potential 24-disks server.

Definitely a NICE number !! Amazing that we can now have that much storage in a single case Yep.. almost 0.2 petabytes... two more like this and I'll be able to take my work home...

Wow! Just... wow!

As far as I know, unRAID does not support USB 3.0. It does not support USB of any kind for array drives. Ah!.. I was thinking about external USB enclosure as of out-of-array storage... inertia of thoughts. (If inertia of my thoughts is HUGE, doesn't it mean that my thoughts are at least BIG? )

As far as I know, unRAID does not support USB 3.0.

And in my setup this would be 184 TB in single array... instead of 113 TB in two... and cost $5,980... hmmmm....

Please update us when you find out what works. Reported in this topic.

Attached the third PDF showing speed test when in RAID-0 configuration for cache drive (previous post wouldn't take it because of size restrictions). Note that RAID-0 is built out of two 2TB drives (Samsung 5400 + Hitachi 7.2 k) so it's very much less than optimal, but still considerably faster than a single 3TB 7200 drive. DiskSpeedTest_Front_2014-12-06-2133.pdf

Just reporting my findings. Addonics AD4SA6GPX2 ( 6G 4-port SATA PCIe 2X controller, Marvell 88SE9230 chipset), $55+$8 shipping at Addonics online store. It supports 4 drives directly as individual drives, or in RAID (RAID 1, 0, 10, SAFE (?) or JBOD - a single large drive), or up to 7 individual drives with use of a 4-drives port multiplier (I did not test this 7-drives functionality). Test platform: Supermicro H8DME-2 mobo, unRAID Pro 6.0-beta2. Pros: 1. Inexpensive hardware RAID. 2. For individual drives, the card is pretty much plug-n-play - insert, connect drives, boot up - it works. I did parity rebuild and parity checks - no problems. I did not do preclear. 3. Hardware RAID - no drivers needed as long as your OS has built-in AHCI inbox driver support (unRAID 6.xxx, apparently, has it) 4. Fast - drives speed tests with jbartlett's diskspeed.sh show no difference from Supermicro SAT2-MV8 cards, which are PCI-X. Cons: 1. In RAID configuration, seems to be not reporting drives temperature (expected). 2. In RAID configuration, seems to be not going to spindown (unexpected). Updated: it does go to spindown. 3. Takes 8-10 seconds to boot, adding to already slow reboot time. 4. To configure RAID, your have to catch the (short) moment of the card black boot screen to hit Ctrl+M. Luckily, configuration itself is very easy, and RAID initialization is instantaneous. Conclusion: I needed hardware (i.e., no hassle) RAID-0 for faster unRAID cache drive, for that purpose this card fits the bill perfectly. It also works as RAID-0 for parity drive - parity rebuild and parity check worked no problems, so if you need big and fast parity and have drive slots available, go for it. Using it for driving individual drives might be not economical - AFAIK, there are cheaper non-RAID alternatives (read: SYBA). Attached are PDFs showing speed test results. DiskSpeedTest_Front_2014-12-06-1955.pdf DiskSpeedTest_Front_2014-12-06-2035.pdf

It depends, but, I would say, close enough. The 4TB are currently the sweet spot in terms of price per terabyte (~$25/TB for green drives, ~30/TB for NAS-type drives). And the prices keep falling now with the 6TB fully in the market. Correct. Correct.

Please update us when you find out what works. Sure, but please note that the Wiki is still locked

Your might want to consider this card: Addonics AD4SA6GPX2 ( 6G 4-port SATA PCIe 2X controller, Marvell 88SE9230 chipset), $55+$8 shipping at Addonics online store. It supports 4 drives directly or in RAID configuration, or up to 7 drives with use of a 4-drives port multiplier. I've installed this card for experiments in my unRAID 6-beta2 server (Supermicro H8DME-2 mobo), configured 2-disks RAID-0 for cache drive - it worked right away. I've reconfigured it as 2-disks RAID-0 for parity drive - it's working, rebuilding parity right now. Next experiment will be to check if unRAID will see individual drives via this card, and eventually, a 4-disks RAID-0 for cache drive.

Interesting. Thanks for the heads-up. I hope you'll be able to return it. Manufacturers (all of them, not just Seagate) have being trying to prevent "pulling out" from external enclosures for many years. First they started making single-use enclosure cases. Then they replaced separate USB electronics with schematics built-in into the drive itself, so that "external" drive does not even have standard SATA connectors. Now this - crippled firmware, this is one really dirty trick if its true. Marketing policies are like martian language to me...