Context-sensitive news, just as I'm wondering what to do about my lack of storage!
I've been using random 3.5" server drives with an external USB 3.0 dock for a while now. I've been really thinking about doing some kind of RAID setup with one of those 5.25"->4x2.5" backplanes lately, but if 6TB+ drives are coming out soon, maybe I can stop worrying and just wait a while more for the prices to drop.
Re: Supposedly Seagate has a 6TB drive coming out soon too. (Score: 1)
Depends on the dock. Some of my older USB2 docks have a 2 TB limit, while by nearly-brand-new USB3 dock complains at anything over 3 TB.
Because most onboard SATA ports allow hot swap, you can get a passive internal dock like this that will just pass the electrical signal through without messing with it.
But with prices as low as $165 for a 4TB drive on Newegg, it seems like $250 wouldn't be an unreasonable estimate. And now my 2TB RAID 5 array is starting to seem a little small...
[Btw, I was intending to repost the pricing link to Newegg from TFA in my comment, but the |. post box hates it -- which I think is because it contains ampersands...]
Re: disk failure -- my next NAS is most likely going to use a RAID 6 array. With 4 data disks and 2 parity disks, it should be able to withstand having one disk fail, and another disk fail during the time it takes to reimage the replacement for the first disk. Which means that your data is safe unless 3 disks fail within a 24 hour window.
Even with SATA and SAS 6G connectivity, you're still looking at a lot of time for file system verification, backups, even just using dd. I think they're fine for general usage, but the size of them is making a lot of the things I suggested earlier pretty time prohibitive..
Re: I really feel that these sort of disks are starting to be seriously limited.. (Score: 2, Informative)
FSCK is mostly a thing of the past. Smarter backup tools can do instantaneous snapshots with deduplication and more. "dd" is the WORST way to read or write a hard drive, whatever you might be trying to accomplish. And hard drive throughput does keep getting faster as capacities increase, so it's not as big of a hit as you might expect.
If you've got a 6TB drive packed with a few large files (like Blu-ray or HDTV rips) and they don't completely change from day to day, a simple rsync over the network could still be extremely fast.
Re: I really feel that these sort of disks are starting to be seriously limited.. (Score: 1)
I'm mostly in agreement with you, de-duplication and large files do make tools like rsync quite efficent, but there is a lot of "enterprise" use that doesn't fit into those categories, mailstores being a good example..
Re: I really feel that these sort of disks are starting to be seriously limited.. (Score: 1)
For that, you'd use zfs snapshots, and send+recv. Infinitely faster than rsync on large files where only a small portion has changed, because the file system knows what has changed, while rsync has to read and compare the files.
Re: I really feel that these sort of disks are starting to be seriously limited.. (Score: 1)
"Okay then, for when you want a straight binary copy of a whole drive what would you use instead of dd?"
That's a somewhat different goal from the average "backup", but
dd_rescue
or
ddrescue
do what
dd
does, but with greater flexibility.
I've used both in attempts to rescue TiVo drives (well, to rescue the contents before the drive finished dying, actually), with probably as much success as was going to be possible under the circumstances.
New Bigger Drives = Cheaper Smaller Drives (Score: 2)