Having gradually built up my media collection to near the capacity of my 16TB external HDD, I’ve reached the point where I’ll probably need to build a RAID array to keep the collection in one place. Assuming the RAID array will be at least 32TB, I have a few questions:
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From what I’ve read RAID arrays can help mitigate the risk of individual drives failing if extra space is allotted on the hard drives. Assuming a total capacity of 32TB, how much of that space would be reserved by the RAID array for data loss prevention?
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Is there a certain type of hard drive I would have to use? Aside from my 16TB drive, I also have two 2 8TB drives that I’d ideally like to be able to re-use in the RAID array, but have left them in their enclosures for the time being.
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If the hard drives in the array have different transfer speeds, does the array as a whole default to the slowest one?
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Whether the hard drives I already have are compatible or not, what RAID enclosure and hard drives would you recommend?
One thing I will also suggest is looking into https://home.tdarr.io/. It’s software that will re-encode your media to h265, saving you a lot of space. I just set it up on my synology NAS because I am at 80% storage and don’t feel like buying another drive yet.
Are there any drawbacks to h. 265?
I mostly watch Plex on my home network, however I use a Chromecast to watch Plex remote from my location with slow internet. Would this be an issue? Would it make the experience better?
I’m running two external tens and I just bought an 18. I’d love to save some space and I’ll have to buy a drive for a long time.
I am not an expert but I think compatibility is the only significant downside. If your device supports it, you h265 will give you better quality at the same file size.
The general datahoarder hive mind seems to be moving away from shucking and towards manufacturer refurbished drives, see https://serverpartdeals.com/ for example, especially in RAID where you can lose a drive with impunity and warranty is uncomplicated by shucking.
In RAID and similar strategies the redundancy comes from a parity drive, which protects against the loss of one (or more with some schemes) drive, so if you only have two drives of the same size it’s just a mirror (50% of total pool) but you can have a drive die without data loss. With four drives you get to use three of the drives (75%), five you can use four (80%) etc. Classical RAID uses identical sized disks but there are other approaches that allow different sizes e.g. mergerfs + SnapRAID or Unraid, here you lose your largest disk to parity.
RAID is generally faster than the individual drives, e.g. mirroring is nearly twice as fast.
Perhaps go with another 2*8Tb which will get you 24Tb usable and use the 16Tb for offline, preferably offsite backup (remember RAID is not a backup, it protects you from disk failure, but not user error for example accidentally deleting things)
Just be sure there is some gaps between the serial numbers of those hdds.
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RAID for uptime, backups for data you care about. RAID(1+) will keep your data online when a disk fails, but backups are the real way to keep data around if shit hits the fan. For a personal media collection, you might be better served with a non resilient RAID0 (total failure if one drive fails) with a backup around to recover from when that happens. If you do e.g. a raid5 you lose 1 disk of capacity in exchange for 1 disk of resiliency, raid6 same but 2 disks. That gives you some safety but there are a lot of instances where those raids don’t save you from losing all your data. If you buy 4x 18TB drives, you could have 36TB from the 1st two drives and then backup to the other two drives.
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There’s no specific type of drive to worry about unless you’re doing RAIDs especially with ZFS. Search shingle RAID rebuild for the biggest thing to worry about there.
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Almost always, yes. Slow drives throttle the rest.
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I’ve never used them but people say good things about synology most of the time. Everything comes with a cost and it’s hard to make any sensible recommendations without knowing your constraints; primarily your budget.
Want to echo what was said here. RAID is not a backup solution. RAID is for always on capability. Do not use RAID as a way to keep valuable data safe. Just have double the drive space and keep a backup of the data on the second drive.
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