41–50 of 314 posts
> The 4 TB HGST drives have roughly 6000 hours on them after ten years. So they mostly sit idle? Mine are about ~4 years old with ~35,000 hours.
To quote myself from a few lines below that fragment: > My NAS is turned off by default. I only turn it on (remotely) when I need to use it.
I know it's not a guarantee of no-corruption, and ZFS without ECC is probably no more dangerous than any other file system without ECC, but if data corruption is a major concern for you, and you're building out a pretty hefty system like this, I can't imagine not using ECC.
Slow on-disk data corruption resulting from gradual and near-silent RAM failures may be like doing regular 3-2-1 backups -- you either mitigate against the problem because you've been stung previously, or you're in that blissful pre-sting phase of your life.
EDIT: I found TFA's link to the original build out - and happily they are in fact running a Xeon with ECC. Surprisingly it's a 16GB box (I thought ZFS was much hungrier on the RAM : disk ratio.) Obviously it hasn't helped for physical disk failures, but the success of the storage array owes a lot to this component.
Earlier quoted context omitted.
It can be luck, but with 24 drives, it feels very lucky. Somebody with proper statistics knowledge can probably calculate the risk with a guestimated 1% yearly failure rate how likely it would be to have all 24 drives remaining. And remember, my previous NAS with 20 drives also didn't have any failures. So N=44, how lucky must I be? It's for residential usage, and if I need some data, I often just copy it over 10Gbit…
it's (1-p)^24^10, where p is drive failure rate per year (assuming it doesn't go up over time). so at 1% that's about 9% or a 1/10 chance of this result. Not exactly great, but not impossible. the backblaze rates are all over the place, but it does appear they have drives that this rate or lower: https://www.backblaze.com/blog/backblaze-drive-stats-for-q2-...
I’ve heard the exact opposite advice (keep the drives running to reduce wear from power cycling). Not sure what to believe, but I like having my ZFS NAS running so it can regularly run scrubs and check the data. FWIW, I’ve run my 4 drive system for 10 years with 2 drive failures in that time, but they were not enterprise grade drives (WD Green).
Hard drives are often configured to spin down when idle for a certain time. This can cause many spinups and spindowns per day. So I don't buy this at all. But I don't have supporting evidence that back up this notion.
OTOH, when the NAS spins up a single disk again, I haven't notice any additional load. Presumably, the read operation just waits until the disk is ready.
Ca't help but wonder how much electricity would have been consumed if you had left it on 24/7 for ten years...
A typical 7200 rpm disk consumes about 5W when idle. For 24 drives, it's 120W. Rather substantial, but not an electric kettle level. At $0.25 / kWh, it's $0.72 / day, or about $22 / mo, or slightly more than $260 / year. But this is only the disks; the CPU + mobo can easily consume half as much on average, so it would be more like $30-35 / mo.
And if you have electricity at a lower price, the numbers change accordingly.
This is why my ancient NAS uses 5400 RPM disks, and a future upgrade could use even slower disks if these were available. The reading bandwidth is multiplied by the number of disks involved.
Surprised to not find 'ecc' on that page. I know it's not a guarantee of no-corruption, and ZFS without ECC is probably no more dangerous than any other file system without ECC, but if data corruption is a major concern for you, and you're building out a pretty hefty system like this, I can't imagine not using ECC. Slow on-disk data corruption resulting from gradual and near-silent RAM failures may be like doing regu…
Edit: ZFS for home usage doesn't need a ton of RAM as far as I've learned. There is the 1 GB of RAM per 1TB of storage rule of thumb, but that was for a specific context. Maybe the ill-fated data deduplication feature, or was it just to sustain performance?
I’ve heard the exact opposite advice (keep the drives running to reduce wear from power cycling). Not sure what to believe, but I like having my ZFS NAS running so it can regularly run scrubs and check the data. FWIW, I’ve run my 4 drive system for 10 years with 2 drive failures in that time, but they were not enterprise grade drives (WD Green).
Keep them running.
Why?:
* The read/write heads experience literally next to no wear while they are floating above the platters. They physically land onto shelves or onto landing zones on the platters themselves when turned off; landing and takeoff are by far the most wear the heads will suffer.
* Following on the above, in the worst case the read/write heads might be torn off during takeoff due to stiction.
* Bearings will last longer; they might also seize up if left stationary for too long. Likewise the drive motor.
* The rush of current when turning on is an electrical stressor, no matter how minimal.
The only reasons to turn your hard drives off are to save power, reduce noise, or transport them.
Earlier quoted context omitted.
To quote myself from a few lines below that fragment: > My NAS is turned off by default. I only turn it on (remotely) when I need to use it.
I loved the idea around the 10Gb NICs but wondered what model switch are you connecting to? And what throughput is this topology delivering?
Surprised to not find 'ecc' on that page. I know it's not a guarantee of no-corruption, and ZFS without ECC is probably no more dangerous than any other file system without ECC, but if data corruption is a major concern for you, and you're building out a pretty hefty system like this, I can't imagine not using ECC. Slow on-disk data corruption resulting from gradual and near-silent RAM failures may be like doing regu…
Big (large radius) fans can move a lot of air even at low RPM. And be much more energy efficient.
Oxide Computer, in one of their presentations, talks about using 80mm fans, as they are quiet and (more importantly) don't use much power. They observed, in other servers, as much as 25% of the power went just to powering the fans, versus the ~1% of theirs: