PCI RAID Card

Recommendations? I'm building up my smallish server at the house.

I was thinking of running 3 1.5-2TB drives in RAID 5. I'm not as much concerned about speed as I am about redundancy so that's why I'm thinking RAID 5.

The case I'm gonna run will only allow 3 drives (for now).

So requirements:

PCI
3+ SATAII Ports
RAID 5 Support


I was thinking something like this... http://www.newegg.com/Product/Product.aspx?Item=N82E16816132017 though I know nothing about the brand.

If you can manage PCI-E the Dell Perc 5i card can be found for under $100 used and most of the time completely untouched, just pulled from new Dell servers. It's a great card with a BBU and works well.
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Failure is just success rounded down.

Scrap the idea of drive pooling in Windows Home Server?
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Unless proven otherwise, you are a 50yr old man with a bucket of KFC in one hand and your penis in the other.

No PCI-E on the board I'm using.
Not using WHS, running Windows Server 2008.

Well, think carefully about how important the data is to you. RAID5 is generally regarded to be a poor choice with 1tb+ drives simply because of a high possible fail rate during rebuilding. RAID6 is a much safer choice but you'd need more drives and in that scenario you might as well just do RAID1 since your number of drives is so low.
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Failure is just success rounded down.

I may be able to go up to 4 drives. I did find a 4bay hot swap housing that only takes up 3 bays.

Data will be important but probably not end of the world if I lose it. I have my truly important files backed up on a portable drive in a firebox.

With 4x1.5TB drives:

RAID 1 = 6TB Usable (No Redundancy!)
RAID 5 = 4.5TB Usable
RAID 6 = 3TB Usable
RAID 1+0 = 3TB Usable

Most of the data that I'm gonna migrate over to it is sitting on independent disks anyways so any redundancy is better than what I've got.

I'm still leaning to RAID 5 but I could be convinced to go to RAID 6.

RAID 6 doesn't help though

If you have seven 2TB disks in RAID5 and you lose one drive, you have something like a 62% chance of losing the array during rebuild.

Now add one drive and make it eight 2TB drives in RAID6... your chance of URE is 62%*62% , or 38%

Make backups and plan on failures.

It's not about the percent chance of failure as a static number though, it's about the amount of data per drive and the performance of the RAID while it is rebuilding. RAID5 is not as stable and takes longer. I will say that I am not clued into the entire methodology of the masses on this one, but 1tb+ drives and RAID5 are generally not recommended.
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Failure is just success rounded down.

The performance of a RAID6 during rebuild is going to be even worse than RAID5, as you're writing two stripes across the entire array.
RAID6 does not fix anything on these high-density drives, it doesn't even cut the chance of array failure in half. When you exceed 23TB on a RAID6 array, it has the same likelihood of failure as a RAID5 array.

It's getting to where you need to concatenate mirrors on these high density drives.

Enterprise hard drives aren't big for the reasons mentioned. They're 300-600GB tops.

MTDL = Mean Time to Data Loss

MTAF = Mean Time to Absolute Failure

So.... both of you.....

What would you recommend then? If both RAID 5 and RAID 6 have issues with large drives what would be the best case?

Like I said I'm not entirely concerned about speed, it's all going to be network transfer anyway, redundancy is nice but if I lose it.... oh well.

RAID1, or just do manual backups. If you don't need everything on a single volume it would be easier and cheaper for you since you could just buy a pci sata controller.
_________________
Failure is just success rounded down.

and here I was thinking RAID 5 was where its at.....WHS Storage pool is looking better and better
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EVGA GTX 1080 TI

It definitely IS where it's at, but not with gigantic drives.
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Failure is just success rounded down.

then whats the point......I mean hell do they even make drives under 1tb now?
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Core I7 4790K @ 4.7 Ghz
Corsair H115i AiO 280mm Water Cooler
EVGA GTX 1080 TI

Oh I have to revise my statement.

The behavior of the RAID 5 was historically as follows:
If 1 Drive is lost and URE occurs during rebuild, stop rebuilding.

The behavior of what some vendors were touting as RAID6 during that time was as follows:
If 1 Drive is lost and one URE occurs, offline the first parity stripe and rebuild with the other parity stripe. If another URE occurs, stop rebuilding.


Today:
Most RAID5 firmware will just offline the data stripe in particular if a URE occurs during rebuild. The rest of the array will rebuild.

RAID6 today attempts to rebuild with the XOR stripe. If the XOR stripe does not compute for some reason, the ECC from the second non-data stripe is tried. The second non-data stripe isn't parity bits (It is unlike the first, XOR stripe), it's generally Reed-Solomon codes. This is similar in many ways to what PAR2 does (it also uses Reed-Solomon) for Usenet/BitTorrent.
So the odds of having a URE somewhere on the data or XOR stripe are pretty low already... but the odds of having a URE on the adjacent Reed-Solomon stripe are even lower, by orders of magnitude.

Desktop drives generally have a URE rate of 10^14. There are some exceptions here, namely the WD20EADS and similar drives. They have a URE rate of 10^15.

I would build RAID6 if it were general storage.

The important thing to know is that this data is not forever.... this is a transitive state.
Storage is not archival and vice versa.
In many ways, archival of important information is more important than online storage of important information.

I've got a WHS and I love it. We've definitely had arguments but she's always been there when I need something.

What kind of data are you planning to store? Do you need it to all to be redundant? WHS is one option for drive pooling but you could do something similar in Server 2008 with folder mirroring software. Pick the folders you want to be redundant and have software push those files to more than 1 drive. For the folders you don't care as much about, don't mirror them so you don't waste space. If you lose a drive, you only lose what was on that drive and not mirrored. If you need more space, add a drive and alter the mirroring configuration.