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Case with 9+ hard drives & OpenSolaris/ZFS advice

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geoffreak:
So my Drobo randomly glitched up and "forgot" everything, so I'm thinking about getting a more serious solution. From what I can find ZFS is the cheapest and most reliable solution (RAID cards are much too expensive and offer none of the awesome features provided by ZFS).
 
First I need a computer that can house my 9 hard drives (4x 2TB, 5x 1TB) and maybe more in the future. I don't plan on gaming or outputting video with the computer, just file storage. ZFS requires a moderately powerful processor and a decent amount of memory to run well, but I don't want to buy top of the line for cost reasons. Cost is not the most important issue for me (it is still important though), but rather noise and power drain. I already have the hard drives, so there's not much I can do in that department, but if everything else was low powered and the PSU only provided enough to power the necessary parts, that would save big on the electric bills.
(Is there such a device that could hold hard drives and run an OS supporting ZFS, but connect to another computer via Firewire?)

OpenSolaris, while technically discontinued, provides the best free implementation of ZFS, so I'm thinking about going with that, but I don't know what hardware is supported by it.

I know I'm just kind of rambling, but any advice anyone could give would be much appreciated.

kureshii:
Best advice on my end is to wait for a stable, mature implementation of btrfs.

1) It is generally not advisable to use an OS that is out-of-development, or even discontinued, for a long period of time, especially for a non-testing machine. I don’t think this needs very much explaining.

2) You want something that is cheap, holds nine 3.5" hard drives, uses as little power as possible and can use ZFS (or comparable solutions) as a filesystem. If that is not a low-end PC, I don’t know what it is.

3) ZFS is not worth shoehorning your system hardware for, if you are a user looking for cheap. I say this as one who spent a year trying to decide what parts to use in a ZFS/OpenSolaris home server, and eventually gave up and decided to stick with plain ext3/Linux while waiting for btrfs to mature.

4) If you must have ZFS and no other filesystem, I would suggest looking for it on an OS that is still being actively developed, e.g. Nexenta or BSD. I’m not quite ready to trust terabytes of data to ZFS-on-FUSE, nor willing to wait for IllumOS to pick up speed and then stabilise.

[edit] Might be of interest.

Pentium100:
Well, I cannot advise you about the OS, but I have this case and it's quite good - CoolerMaster Stacker810. It has 11 5.25" bays and comes with one 4-in-3 drive module (it fits 4 3.5" HDDs and takes up 3x5.25" bays, also as a 12cm fan). Buy two additional modules and you can place 12 drives in 9 bays. Two additional drives can be added with regular 3.5" to 5.25" adapters. Also, if you really need drive #15 you can remove the power etc buttons and have one more 5.25" bay.

The build quality is also good.

My PC with that case has 8 hard drives (2xSATA, 1xSCSI, 5xIDE), a DVDRW drive, a DDS-4 tape drive and three empty bays for one more 4-in-3 module.

geoffreak:
@kureshii
It's not that I won't use any other solution besides ZFS, it's just that I use a drobo and in theory, ZFS is the only better filesystem than BeyondRAID. This is more future planning than anything and I likely won't buy anything just yet.
I'm not picky in regards to OS so long as it is free and supports unix-styled commands. A nice GUI with at least some application support (ie Firefox) would be nice though. (Linux is my preference though, so I'll be watching btrfs development)
The only thing I need to know is what hardware is supported because I'll need to make sure to get a compatible motherboard and a JBOD SATA card (as most motherboards can't directly support this many drives)

@Pentium100
Sadly it appears that the case you have specified is no longer sold (at least at NewEgg), but the 4-in-3 module is cheap and should work in any case that has a lot of 5.25" bays. Thanks for the idea!

kureshii:
I am a little confused by your expectations; ZFS is a filesystem indeed, but BeyondRAID is a RAID implementation, not a filesystem, as far as I can tell (the Drobo probably has its own filesystem implementation, but I do think when you speak of BeyondRAID you are comparing it to RAID-Z, not ZFS). Perhaps what you mean to say is “RAID-Z is the only better RAID implementation than BeyondRAID”?

Here I would like to point out that Linux has its own RAID implementation in the form of mdadm, and it is already at a rather mature stage. When used with LVM2, the logical volume management module, it easily matches ZFS/RAID-Z feature-wise, although it is still susceptible to the RAID-5 write hole.

One critical thing to note about ZFS, as of the time of writing, is that it does not support RAID expansion. What this means is that if you already have a 4-disk RAID-Z/RAID-Z2 array, you cannot expand it at a later date by adding one more disk to the array. This was one of the critical flaws of ZFS (for a home user; let us not speak of enterprise usage here) that led me to decide on LVM2 instead (yes, mdadm/lvm2 on linux allows you to do RAID expansion).

I had been keeping some tabs on development in this area; last I read is that Adam managed to come up with a sketch for implementing this. But now that he and many other ex-Sun engineers have left Oracle for other projects, I find it highly unlikely that Oracle will ever add this feature to ZFS, considering the lack of enterprise interest in this area (enterprises often expand their storage pools by adding an entire array, rather than expanding existing ones. Such a feature is low on their priority list).

If you ever decide to expand your RAID-Z array, you are going to have to back up all data on it first, and rebuild the array from scratch. Not a minor undertaking for a non-enterprise user by any means if you have data running in the terabytes, and no spare disks.

It just occurred to me that there is no cheap motherboard (~$100) in existence (that I know of) that has at least nine SATA ports. Higher-end motherboards have up to ten (with a secondary on-board controller), but those are often meant for higher-power systems (X58 chipsets and the like), which runs against your idea of a low-power file server.

Even with such a ten-port SATA system, there is something to be said for not putting all your disks on the southbridge; apart from the AMD 890GX and Nvidia nForce series, neither of which are particularly low-power, pretty much all southbridge interconnects have a maximum bi-directional bandwidth of 1GB/s, and I have not heard of any consumer-level southbridge managing over 700MB/s. If you are going to try to implement FireWire and/or gigabit LAN connectivity, that southbridge interconnect is going to get very crowded. Even getting a cheap four-port SATA controller on the northbridge PCIe slots would alleviate that load quite a bit.

A cheap motherboard with a decent southbridge (ICH10 or maybe SB750+), plus an additional disk controller (RAID or otherwise), is a cheaper and more power-efficient solution. Here I readily assume you will be running the file server with onboard graphics.

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