Say I'm comparing 8 x 4TB vs 4 x 8TB for a new RAID-Z2 setup. Or 10 x 4TB vs 5 x 8TB, or 8 x 1TB vs 4 x 2TB - the quantity and capacity of drives is somewhat irrelevant here. This will be for a home NAS, where file integrity is key above all else. There will be very few concurrent users, and I don't plan on hosting VMs or Plex or databases or anything like that on this box.
Let's assume, for argument's sake, that the total cost of ownership of both choices is identical (so, my case and motherboard can fit as many drives as I need, my electricity provider magically decides to charge me a flat rate for my server regardless of how much power it uses, both new and future replacement drives are identically priced, etc) or at least the price difference is negligible - what are the benefits and drawbacks of each approach? I'm not particularly well versed in this stuff, but here are my assumptions:
More lower capacity drives:
Con: More drives means greater likelihood a drive will fail
Pro: Smaller drives means lesser likelihood another drive will fail during resilver, since resilvering will be quicker
Con: Higher power draw, more heat, more vibration, more noise
Pro: More usable drive space
Con: (theoretically) more difficult to find replacement new drives of the same capacity as time goes on
Logically, the opposite of all of the above would apply to less higher capacity drives:
Pro: Fewer drives means lesser likelihood a drive will fail
Con: Larger drives means more likelihood another drive will fail during resilver, since resilvering will be slower
Pro: Lower power draw, less heat, less vibration, less noise
Con: Less usable drive space
Pro: (theoretically) easier to find replacement new drives of the same capacity as time goes on
What other considerations are there to each approach? Is there a 'correct' answer? Are my assumptions accurate? From what I can tell, more lower capacity drives has the benefit of more usable space and less likelihood of failure (potentially offset by smaller drives generally having an older manufacture date than larger ones), whereas fewer larger drives will have less power usage/heat/vibration, and probably a lower overall cost.
Am I way off the mark here? Any advice is greatly appreciated
Let's assume, for argument's sake, that the total cost of ownership of both choices is identical (so, my case and motherboard can fit as many drives as I need, my electricity provider magically decides to charge me a flat rate for my server regardless of how much power it uses, both new and future replacement drives are identically priced, etc) or at least the price difference is negligible - what are the benefits and drawbacks of each approach? I'm not particularly well versed in this stuff, but here are my assumptions:
More lower capacity drives:
Con: More drives means greater likelihood a drive will fail
Pro: Smaller drives means lesser likelihood another drive will fail during resilver, since resilvering will be quicker
Con: Higher power draw, more heat, more vibration, more noise
Pro: More usable drive space
Con: (theoretically) more difficult to find replacement new drives of the same capacity as time goes on
Logically, the opposite of all of the above would apply to less higher capacity drives:
Pro: Fewer drives means lesser likelihood a drive will fail
Con: Larger drives means more likelihood another drive will fail during resilver, since resilvering will be slower
Pro: Lower power draw, less heat, less vibration, less noise
Con: Less usable drive space
Pro: (theoretically) easier to find replacement new drives of the same capacity as time goes on
What other considerations are there to each approach? Is there a 'correct' answer? Are my assumptions accurate? From what I can tell, more lower capacity drives has the benefit of more usable space and less likelihood of failure (potentially offset by smaller drives generally having an older manufacture date than larger ones), whereas fewer larger drives will have less power usage/heat/vibration, and probably a lower overall cost.
Am I way off the mark here? Any advice is greatly appreciated
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