Seriously though, chances are you have experienced silent corruption on your 4 year old system without even knowing it.
Maybe so, but to date I have not actually encountered problems/lost data resulting from that.
Just because ECC is not typically used in your so-called home systems, does not mean it should not be.
Agreed, but the vast majority of consumer motherboards tend to be non-ECC, and since I had never had any data issues with memory previously, it did not occur to me that I might require a more reliable RAM solution.
It is true that drives stay spinning in FreeNAS by default, but it is not that hard to make them spin down.
Thanks for the link, perhaps spin-down was the wrong term. "Reduce activity" to save on wear and tear, which is what the WD Green idle state seems to be trying to achieve.
However, the reigning theory (I'm not aware of clear data either way) in the FreeNAS world seems to be that drives last longer if they stay spinning than if they start/stop, maybe even once a day.
That's taken up some of my time researching. I can't find any statistical evidence on the web weighing up lifespan reduction from being left running vs that done by start/stop events at differing frequencies. Would be helpful to know.
ZFS has robust mechanisms to ensure data integrity...
ZFS can identify and correct errors...
Agreed, and I like that fact, however by "more prone to data corruption due to memory hiccups" I meant that ZFS appears to have a critical dependency on the memory state of the system.
An ext4 formatted drive may sit there quietly with infrequent access, and if a memory glitch occurs it's more likely to affect the running system than the data held (granted unless the memory space in question is holding data about to be written to the disk).
However, ZFS appears to be continuously checking data on the disks to protect them, but does so assuming that the memory space is 100% uncorrupted; a memory glitch while running ZFS can result in data at rest being corrupted (I've read posts about entire storage spaces being lost, not sure how accurate that is).
Granted, the ext4 disk will be more prone to all manor of data corruption problems, same as NTFS or other journaling systems, so I think "self-healing" ZFS-like file systems are the way to go to protect data. I just had not realised the critical dependency on using ECC RAM.
Leaving the disks spun up does not cause appreciable wear and tear. Constantly parking and unparking the heads, as WD Green drives will do by default, does. This is behavior that can be easily modified by a WD-sanctioned tool, if you choose to use WD Greens (as many people do). If you believe (contrary to any available evidence) that leaving your disks spun up is bad for them, you'll probably be better off with a system other than FreeNAS. There are workarounds, but you seem to be starting from a faulty premise.
Indeed, my faulty premise was that the drives spun themselves down. I clearly had not understood the true nature of the idle mode for these drives.
This is not normal. I don't know off the top of my head what the problem is, but it definitely isn't normal or expected behavior.
I know, happens about every other day for me. I'm wondering if its a browser compatibility thing rather than a problem with the web host.
The problem is that throughout your life you've probably had errors and there was no way to identify the cause. ZFS can identify (and correct) this kind of problem.
None that lost me data (touch laminated substance this monitor is parked on).
Do note though that the wdidle thing will still be required on Linux, so don't think that switching OSes will get you out of the woods with that.
Why? My last storage backup was Linux and had WD Greens, as per above it has lasted 4 years. It's OS was mounted on a separate HDD, and the Greens only held data backups, so they were not being periodically poked by running processes.
I admit that the problem is not really a FreeNAS issue, but my use of the WD Greens in a system that is constantly performing checks on the data, a necessary part of the protection of the system. I picked the Greens because of the success of my previous drives, but am now starting to think I should have gotten different ones.
I haven't actually tried the original suggestion for redirecting the .system data to a separate drive, although I note several other posts around from people who have done so.
As I noted in the thread you wrote (I happened to reply just seconds before reading this thread) you aren't using recommended hardware. So I'm not the least bit surprised that you aren't having a great experience with it. That's literally par for the course. We've got lots of people that don't use recommended hardware. Statistically they are much much much more likely to have problems than those that take our recommendations seriously.
Unfortunately I read the FAQ on the freeNAS site and didn't really research it beyond that. As you noted in your other post (I'll respond separately), the real gotcha for me here was the non-ECC RAM. wdidle the drives would not have been a big issue, but the potential to lose swathes of data from a memory glitch is a biggie.
Thanks, I ended up building a bootable FreeDOS USB for this.
I would agree that FreeNAS isn't for your "typical home" setup. It's for those people that are neurotic about their data and want to protect it long-term and are willing to pay for extras like server-grade parts and ECC RAM to ensure their data is safe.
And that's the kicker, at the time I purchased hardware based on previous recommendations for building a home server with Linux. FreeNAS (or ZFS more specifically) has its own set of requirements.
Thank you everybody for your feedback, this has been an enlightening day.
For the time being I'm going to revert back to a Ubuntu/ext4 USB system just so that I can use the drives as is for the near future without killing them in the process.
It's not a good long term solution, but I think realistically I'm going to have to swap out some of my hardware to ensure the reliability of the ZFS system before I try to use it in anger. *sigh* let the savings begin...
Thanks again,
Rob.
