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Silent file corruption is the reason why I now keep all my data on a ZFS filesystem. ZFS has a checksum for every block and if you have redundancy at all (raidz, raidz2, or even just tell ZFS to keep two copies of each file) then it will repair the corruption as well as detect it. I've got a HP Microserver running Solaris but I recommend running FreeNAS instead if you don't know ZFS. This blog is a good place to learn about ZFS.

ZFS is used in production on FreeBSD by some people and I generally like the ZFS features, but I don't view ZFS as really production ready on any OS.

This is because ZFS on any OS does sometimes lose all access to the zpool (i.e. you lose the entire set of RAID volumes and filesystems on them, all at once) due to ZFS bugs, and there is no fsck. I can't think of another filesystem where you can (a) lose all access to your files and (b) there is no fsck. Same goes for RAID - even if you use RAID-1 with ZFS you can still lose your entire zpool due to a ZFS bug.

Given that the "no data loss by design" (can't find the reference for this, perhaps Sun/Oracle has stopped saying this) hasn't really worked out for ZFS on Solaris or FreeBSD, there is still a need to have a complete backup of any ZFS zpool (as with any other RAID / filesystem). The checksumming, COW, snapshots, and self-healing data (for RAID) are very nice, but losing your whole pool due to a ZFS bug means it isn't really a high availability solution. On the plus side, it does make it very easy to snapshot in order to take a backup, and makes incremental backups easy with zfs send.

Here are a few samples of complete zpool loss:

http://opensolaris.org/jive/thread.jspa?threadID=132089&tstart=120

http://superuser.com/posts/130822/revisions - FreeBSD

http://www.mail-archive.com/zfs-discuss@opensolaris.org/msg39578.html

My point is not that ZFS is a bad idea, but it really needs an fsck (see http://www.osnews.com/story/22423/Should_ZFS_Have_a_fsck_Tool_ ) and anyone using ZFS must have full backups onto another server of the whole zpool, perhaps into a non-ZFS filesystem to avoid software bugs that hit both the main and backup zpool. The need for backups isn't unique to ZFS but I haven't seen other filesystems/RAID implementations promising "no data loss by design"

http://breden.org.uk/2009/05/01/home-fileserver-a-year-in-zfs/ has some good info on using ZFS for a home NAS, with a separate backup server also using ZFS.

btrfs isn't mature yet, but its designer has said he will always make fsck a priority over new features: http://lkml.indiana.edu/hypermail/linux/kernel/0706.2/1284.html

Actually, the track record of nuclear is excellent. In the West, a single accident nearly 40 years ago (TMI) with no victims. In fact, if all the other energy-producing methods were held to the standards of nuclear, you could never afford anything else...

Only one accident in the US in 40 years? HAHA!!! Here's a list of nuclear accidents in the US. Even France has had spills. Wiki has another list of nuclear and radiation accidents.

Ask the Navajo, Sioux, and all the others where uranium is mined if it's held to high standards.

Wind and solar will always only provide for peak demand, through massive overcapacity, because even occasional blackouts are unacceptable. You need a base supply, and if you cannot get hydro, the only clean alternative is nuclear.

Nuclear power is NOT clean. Geothermal however is relatively clean and can be used as a baseload energy source.

Falcon

I'll take in my Backyard, I'll take it over ANY Coal fired plant.

As long they build a containment vessel and don't let Russian yahoos run it I am fine with it.

Oh do you mean like any of these:

• Trojan Nuclear Power Plant
• Two French nuclear spills in one month
• Britain's nuclear power plants have suffered more than 1,750 leaks, breakdowns and safety faults in the seven years to 2008.
• Davis-Besse Nuclear Power Station
• The worst nuclear accident in U.S. history: July 16, 1979, Navajo Reservation

Falcon

You are failing to take into account for the costs of nuclear power the vast amoung of money that must be spent on PR and the like

I didn't take the cost of PR into account because neither it nor nuclear power is needed.

to get the public to allow the safest means of mass energy production we have due to their insane and irrational fear of anything with the word nuclear in it.

Not everyone opposes nuclear power because of some nebulous fear. Ask the Navajo about the impact of uranium mining on the Navajo Reservation. Or some First Nations in Canada. Or the Aboriginals in Austrailia. Ask France about the nuclear spills there.

Opensolaris is much easier for first times to set up, check out http://breden.org.uk/2008/03/02/a-home-fileserver-using-zfs/ for a guide that I found helpful.

OpenSolaris 2008.11 runs great, the timeslider is a very useful feature as well.
zfs is quite easy and more reliable than a raid 5 setup.

http://breden.org.uk/2008/03/02/a-home-fileserver-using-zfs/ is a great guide to help you out. I get 45MB/s read and write from a dual parity array with 4 640gb drives. The cpu isn't the most powerful but it gets the job done.

I recommend using ZFS on OpenSolaris. Create one massive storage pool from multiple drives, and then create as many file systems as you require. Each file system consumes as much of the storage pool as it needs, and if required, a file system's space can be constrained or guaranteed using quotas and reservations. Thus, no shrinking is required. Also, Solaris has Zones you can run other OSes in too. See here: http://breden.org.uk/2008/03/02/a-home-fileserver-using-zfs/

This is quite timely as I was starting to investigate the use of microgeneration recently and wrote some stuff yesterday. I think this has potentially great benefits to society, as well as reducing greatly one's utility costs. If of interest, I collected up my thoughts so far on this subject here: http://breden.org.uk/2008/08/11/microgeneration/

Here is the direct URL for the ZFS articles: http://breden.org.uk/2008/03/02/a-home-fileserver-using-zfs/

Using Solaris Express with ZFS. There is an extensive set of articles on how to do this at Simon's blog http://breden.org.uk/