Can I set up a JBOD for my OWC Thunderbay 4 without deleting data?

oxband

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I have an OWC Thunderbay 4. I didn't realize to use it as a JBOD - which I'm doing - you need to set that up in Disc Utility. I just put in the 4 drives and got to work. I already have lots of data on the drives.

Is there any way to make it a JBOD without deleting everything I have on the hard drives? I've already spent days converting footage from AVCHD to Pro Res. I'd rather not repeat the process.
 

ColdCase

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Feb 10, 2008
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You have the Thunderbay 4 RAID ready box? or the version with the hardware RAID? Does the thunderbay show up as four or one drive now?

When I plugged in my Thunderbay 4, the four drives showed up a separate drives. I used disc utility to configure a mirror set and a RAID0 striped set. What do you want?

When you switch RAID types or JBOD/RAID you typically have to reformat drives. Do you have a backup? One usually reconfigures the drive set and then copies the data from the backup to the new drive set. If you don'y have a backup, get one and save your data there. Playing around with RAID sets can sometimes go wrong. Then reconfigure your disc set.
 

oxband

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oxband

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Sep 10, 2009
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So there's no way to make it faster by re-doing my hard drive set up?

The thing does run a bit slow. The drives are all HGST drives that run at 7200rpm. Any other ideas for why it might be running slow?
 

matreya

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Nov 14, 2009
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The only way to speed things up is if you buy SoftRAID from OWC, backup everything you have on these hard drives to storage devices that are big enough to store all the data, then configure the Thunderbay IV to be RAID5 mode, which will erase all the data on your hard drives. Then restore all your data from the backup drive(s) to the new RAID you've created.

I'm assuming the HGST drives are all the same size?

With them as you have them, you're only going to get a max of about 150MB/sec vs about 400-ish using RAID5.
 

theSeb

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Aug 10, 2010
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That means it's running in JBOD. JBOD stands for just a bunch of disks, which is exactly what you have.

The thing definitely moves kind of slow.
How big are the drives and how full are they? What does "kind of slow" mean to you? Have you run any benchmarks to ascertain the sequential write and read speeds of each drive? What do you use these drives for?

I don't want to do a RAID 0. I want the four drives working separately as a JBOD. It works but it's definitely slow.
That's exactly what you have now. If you don't want RAID, then you're not going to make things faster.

Would it go faster if I did something like this?: http://macs.about.com/od/usingyourmac/ss/raidjbod_4.htm
No, it would not go faster. There is no such thing as JBOD RAID, as the author calls it. There is JBOD, concatenation or span of disks (which is what is being discussed in the article) and then there is RAID.
 

oxband

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If I do a concatenation of disks....are the discs still containing data discretely, each to their own disc? More importantly, will that make it go faster?

I don't want to do a RAID 0 cause I worry about losing everything. But I would like the drives to be faster. (As for speed, I haven't done any tests. But, for example, if I switch between drives in the Finder, it takes much longer than clicking on a stand alone external hard drive where I never get the beach ball).
 

theSeb

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Aug 10, 2010
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If I do a concatenation of disks....are the discs still containing data discretely, each to their own disc? More importantly, will that make it go faster?
No, it will not go faster and it is in theory just as risky as RAID 0. Even though each disk holds data discretely, there will be blocks of files that sometimes are written across the drives. So if file is written across disk 2 and 3 and disk 3 fails, you will lose that file. You may be able to use a data recovery application to recover the other files on disks 1,2 and 4 though. Do note that it's not guaranteed.

I don't want to do a RAID 0 cause I worry about losing everything. But I would like the drives to be faster. (As for speed, I haven't done any tests. But, for example, if I switch between drives in the Finder, it takes much longer than clicking on a stand alone external hard drive where I never get the beach ball).
If you worry about losing everything, then a spanned volume (or concatenation) will not help to alleviate those concerns and gives you just as much risk as RAID 0. I assume that the data on these 4 drives is backed up somewhere? If it's not, then I would address that first, before anything else.

On a side note, it sounds like the drives are going to sleep... have you tried to switch off the allow disks to sleep option in system preferences?

A bit of background reading

Wikipedia said:
Spanned volumes are a non-RAID drive architecture, and may be implemented in hardware or software; they may be referred to as Concatenation, SPAN, BIG, or JBOD, though this latter is ambiguous – JBOD may also refer to each physical disk being presented as a separate logical volume.

Unlike RAID, spanned volumes have no fault tolerance, so if any disk fails, the data on the whole volume could be lost.
This is why I hate it when people refer to a spanned volume as a JBOD, because it is not a JBOD, by it's proper definition. It's frustrating that this sort of ambiguity and confusion is allowed to fester and it impacts users like yourself.
 

ColdCase

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The only way to speed things up is if you buy SoftRAID from OWC, backup everything you have on these hard drives to storage devices that are big enough to store all the data, then configure the Thunderbay IV to be RAID5 mode, which will erase all the data on your hard drives. Then restore all your data from the backup drive(s) to the new RAID you've created.

I'm assuming the HGST drives are all the same size?

With them as you have them, you're only going to get a max of about 150MB/sec vs about 400-ish using RAID5.
No Don't recommend RAID5, just use disc utility to RAID0, then us a backup. A cheaper and more effective for home use.
 
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ColdCase

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I have an OWC Thunderbay 4. I didn't realize to use it as a JBOD - which I'm doing - you need to set that up in Disc Utility. I just put in the 4 drives and got to work. I already have lots of data on the drives.

Is there any way to make it a JBOD without deleting everything I have on the hard drives? I've already spent days converting footage from AVCHD to Pro Res. I'd rather not repeat the process.
Many good pieces of advice here.

In summary, you are using JBOD now.

The interface is as slow as the disc drives you purchased are slow, there are faster drives available for a lot more money.

The only way to speed up using your existing drives is to use RAID, RAID0 is commonly used. You combine two 4TB drives into a single 8TB volume for example. The more discs you add the faster it will be. You loose all data when one disc fails, so you need backup (you need backup for any architecture)

Setting up RAID overwrites all data on the disc(s)

Disc utility works great for RAID0 or RAID1 (mirror)

I routinely RAID0 two drives for my working volume.

Hard drives will begin to slow down noticeably when the reach ~ 50% capacity

SSDD is faster.
 

oxband

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Sep 10, 2009
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I dont have the ability to backup the drives (it's 16 TB of data from a film I'm working on and backing it up would cost a lot). I do have all the AVCHD files I expand to make movie files backed up. My options seem to be stick with the JBOD and accept the fact it's a bit slow or go RAID 0, get faster speed, but risk having to export all my movie files again if it stops working.

Thoughts? I'm inclined to go for the slower speed. I'm not doing anything graphics intensive.
 

matreya

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Nov 14, 2009
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No offence intended, but if you have 16TB of important data, not having a backup of your work is asking for trouble.

If you can afford it, I would buy another Thunderbay 4, and do what Coldcase suggested. Setup the 2nd Thunderbay with 4 x 4TB HGST Deskstars as RAID0 with Apple's own Disk Utility. Copy all the data across, then setup the 1st Thunderbay as RAID 0 as well, then setup a backup regime using something like Carbon Copy Cloner to regularly mirror the new Thunderbay with your content to the newly reformatted original Thunderbay.
 

oxband

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No offense taken. I appreciate the advice.

To be able to get enough data to back it up would cost over 1k. I have backed up the cards I used to create the movie files so if it ever crashed, I'd only need to retransfer those cards into movie files. I get it's risky. But given the fact it's a rectifiable problem, I'd rather not spend the 1k.
 

ColdCase

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Yes, the keeping backups of the original source and take the transcode time hit should the working drives fail is a strategy many of us used until we built up sufficient storage. A good strategy for home use. Although new stuff is pretty reliable, I just wanted you to understand the risk. I've run RAID0 for several years without a hiccup. I've had more issues with RAID1 mirror, but thats probably more of a luck of the draw thing than anything else.

So, if you can stand the time, just continue what you are doing. It actually may take more time to configure the drives you have into RAID0 and put all your data back on them than what you would save for the remainder of your project. There is no way to reconfigure the drives now without risk of file corruption, short of buying 16TBs of additional storage.

Video has never been a inexpensive hobby, ether in terms of time or money :)