JBOD, explained

[WitherspoonVideos]

It's Con-Can-Ten-Nated disks

[mafaUtube]

The Zyxel’s manual is written: "If you have two JBOD volumes (with one disk in each), a failure of one disk (volume) should not affect the other volume (disk). (...) Data is not written across disks but written sequentially to each disk until it's full." - ftp://ftp2.zyxel.com/NSA320/us­er_guide/NSA320_4.01.pdf # Video says not. And the truth is...?

[sn0le]

@mafaUtube:

That's if you have 2 JBOD volumes with 1 disk in each,

Not if you have one JBOD volume with 2 combined disks.

Page 165 in the manual:

"When a disk is missing from a RAID 0 volume or a two-disk JBOD volume. The volume is unusable. If you removed one of the disks you should be able to re-install it and use the volume again (as long as you did not change anything on the disk). If a disk has failed, you need to replace it and re-create the whole volume. All data will be lost."

[mafaUtube]

Thank you very much for this video!!! Mafa, Prague, Czech

[TestimentBlue]

he farts at 5:23

[Paulph04]

Forget JBOD, all it gives you is extra space and no performance increase. RAID 0 is far better, as you get the extra performance. And anyway, hard drives are now faster and more reliable than ever before.

[sn0le]

@Paulph04:

Very true.

I made a video in january where I looked closer into the video from Applesoldier and his Mac Pro.

I did tests with JBOD and striping, and the difference in performance was HUGE.

They both have the same disadvantage though.

If one drive fails, you can kiss all the data on the array bye-bye.

And with 3 drives, there is a 3x higher chance of that happening.

Why anyone uses JBOD is a mystery to me. :)

My video is: watch?v=dF2x7aNOnbg

[Paulph04]

@sn0le Yes, the lack of data redundancy as well as there being no performance increase makes JBOD totally pointless. It is possible to have the performance of RAID 0 and the data redundancy of RAID 1 if you go for RAID 0+1, though this needs at least 4 hard drives and suitable support on the motherboard or from a hardware RAID controller. I'm just going to have a quick look at your video now.

[Paulph04]

@sn0le Thanks for your comment. I've just done a RAID 0 stripe on my Windows XP system using 2 160GB WD Caviar Blue's, and I'm getting double the transfer rate I was getting using a single SATA drive.

[mceh273]

SnOle - Good advice for the Apple person. The word you were having trouble with is concatenate. Its pronounced ;

Con Cat (as in pet) En Ate

In means joins together in a series or chain.

I had a look at all you RAID videos and they are extremely easy to understand. Thanks for all the work you put into them to make things easier to understand.

[sn0le]

@mceh273:

Thanks for the tip and the feedback.

Glad you enjoyed my vids. :)

[rlund3]

Pronunciation is similar to concave.

[TALKCalgary]

First class video!

[sn0le]

@TALKCalgary:

Thanks. :)

[grahammj]

why would anyone use JBOD? What is an example of JBOD being an ideal setup?

thanks for the clear explanation

[sn0le]

@grahammj:

I see no use for JBOD.

You get the same vulnerability as with RAID0 (striping).

No redundancy, if one drive fails all the data will be lost.

But with RAID0 you at least get faster reading and writing.

I might be missing out on something, but I see no cases where JBOD is a good solution.

[1982yosef]

Good one man !

[guzano21]

Great man !

[sn0le]

@guzano21:

Thanks. :)

[SciTech09]

Very nice job. Thanks for the info.

[sn0le]

Thanks man. Glad you liked it. :)