I’ve been reading that it’s best to avoid the BarraCuda drives. My intention is to go with the best cost-to-storage ratio HDDs and use that with ZFS and ECC RAM. Whether it’s with CMR or HAMR HDDs, it seems like there are a lot of subjective opinions that higher-tier drives like EXOS will last longer and are more reliable. The cost for those HDDs is significantly higher, and even then, there are no guarantees that there won’t be downtime. My thinking is that with the much cheaper BarraCuda HDDs, I can also buy additional HDDs and dedicate them to parity. Shucking drives may make sense if the price is right, but shucking voids the warranty, so that’s another dilemma.
I’m also reading about SnapRAID. I’m not sure if that can be used with TrueNAS and ZFS. How many parity drives can be set up with TrueNAS and ZFS? Is 2 the max, or can I set up 3 or even 4?
There are no guarantees, only probabilities. More parity reduces the likelihood of downtime (with trade-offs, of course). So does improved drive reliability–if you can reliably ascertain that. So does sound hardware. There are lots of ways of reducing the risk, but none of eliminating it completely.
As to parity levels, ZFS supports RAIDZ3, allowing up to three disks’ parity in a vdev.
My understanding is that Seagate as well as WDD bins their HDDs.
I agree with you, but wouldn’t the probability be higher regarding uptime with parity than the highly subjective “reliability” moniker? How does one ascertain that reliability? That’s sort of why I am shying away from spending more money on WF Gold or Seagate Exos. The amount of money saved will give me the ability to buy an extra drive as a backup or a spare. I would like to consult with the experts here before I spend the money and see how this progresses.
So 3 drives is the max ZFS will support for parity? So on a 4-bay setup, I’ll have 1 HDD for data and 3 for parity?
On an 8-bay setup, I’ll have 5 HDDs for data and 3 for parity?
I think I was reading that SnapRAID supports even more HDDs for parity?
I’m sure you know perfectly well what a video is. If you’re asking for one to explain this, I don’t have one, but you can obviously read. I’d suggest you start with the TrueNAS docs, linked at the top of every page in this forum. I’m also partial to Uncle Fester’s Guide, though since I maintain that I’m probably biased–that link is in my sig.
That’s a reasonable course of action.
Yes, per vdev.
Maybe? SnapRAID isn’t a TrueNAS or a ZFS thing, so I can’t help you there.
My lower tier hard drives have almost 7 years of runtime on them. Three of four are still going, last year the fourth one started to indicate failure was coming. These have 3 year warranties and once those were over, I was going to replace them, and now double the warranty time, still going strong.
My advice, assume the warranty is the life of the drive. Drives are consumables, they will eventually fail. And you have a very real Infant Mortality out there, so when you get new drives, properly test them in an attempt to weed out a bad one before you put it in a pool.
As for SnapRAID, if you visit the site it tells you it is not ZFS, and there are some limitations. I would not mix the two unless you have tested it out in advance and fully understand the limitations.
This boils down to 4-8 TB Barracuda (Compute) being SMR, which is a big NO for use with ZFS. The latest release oh high capacity Barracuda appear to share the HAMR plateform of similar size Ironwolf and Exos M, and should be fine, possibly with some parameter tuning (TLER).
WD did a very fine mess of its Red brand, and Seagete is not immune to stashing very different technologies under the same marketing moniker.
The more time you’ll spend shopping around, and the more experienced you’ll get with sourcing server-grade enterprise parts, the more you’ll find that Seagate Exos, Toshiba MG (do not forget Toshiba…) or WD Gold/HGST Ultrastar may actually come cheaper than Ironwolf, N300 and the rest of the WD rainbow.
Enterprise drives are priced to be sold in bulk at a discount rather than individually, as consumer-facing lines are sold. Some retailers then kindly resell unit drives at bulk price.
