What is JBOD?

x509

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With JBOD does the collection of drives in the JBOD enclosure look like one drive?

How does JBOD compare with normal RAID?

(I'm not being a troll here. I honestly don't know. :censored: )
 

Master_shake_

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JBOD is just that Just a bunch of drives or just a box of drives or whatever.

Your controller or windows will take all the drives and lay them end to end and call it a volume.

I use one with all the leftover drives i had for fun.

Not great for a backup strategy.
 

x509

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JBOD is just that Just a bunch of drives just a box of drives whatever.

Your controoller or windows will take all the drives and lay them end to end and call it a volume.
Thanks for the super quick answer. So what happens if one drive goes bad? Do you lose the entire volume?

So if I have 3 4TB drives and 1 6 TB drive, does that mean that the JBOD looks like 18 TB? (Wow, what would I do with 18 TB? ...)
 

Master_shake_

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Thanks for the super quick answer. So what happens if one drive goes bad? Do you lose the entire volume?

So if I have 3 4TB drives and 1 6 TB drive, does that mean that the JBOD looks like 18 TB? (Wow, what would I do with 18 TB? ...)
Depends which one goes bad.

If you have 4 tb of data and drive one 4tb goes bad you lose everything.

If drive 3 4tb goes bad you don't lose anything.

It's like a game of russian roulette.
 

cjcox

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JBOD is just that Just a bunch of drives or just a box of drives or whatever.

Your controller or windows will take all the drives and lay them end to end and call it a volume.

I use one with all the leftover drives i had for fun.

Not great for a backup strategy.

JBOD actually doesn't imply a "volume" arrangement such as concatenation.
 

acquacow

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If it employs mirroring or striping or even a parity then its' not a JBOD.

how else can it work?
It just presents individual drives to the OS, nothing more, nothing less.

If you put 5 drives in it,5 separate drives show up to the OS.

You can then do OS level raid stuff if you want (which is absolutely fine and works great).
 
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SmokeRngs

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You don't ever use JBOD unless you don't care at all about the data on the disks.
 

jardows

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A common application I see for JBOD is in storage applications using ZFS, where you have a drive controller with many drives attached. Instead of using the controller's RAID functions, you set the controller to JBOD. You then use Z-RAID for redundancy, whether it be mirroring, striping, or parity (similar but not exactly like RAID-5).
 

cjcox

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If it employs mirroring or striping or even a parity then its' not a JBOD.

how else can it work?

JBOD is exactly what it says. It's just a bunch of disks. Therefore they could just be merely presented as individual disks.

The concept of a "span" or concatenation, might be something you could do with a JBOD, I'm just saying, it's not required.

With regards to "striping" not being JBOD, that dosen't necessarily have to be the case. And a lot of that confusion comes from the false idea that RAID0 exists, which in truth, that's a farce.

With regards to "parity", that term usually implies RAID of some sort (again, emphasizing that RAID0 is NOT RAID). Though, I supposed some could find a "parity" example that isn't RAID (we just don't know what the parity is being used for in that case).

If you just really, really, really want to get down to brass tacks, a lot of our old terminology, be that "RAID" or "JBOD", is changing. All flash arrays often times use erasure coding (for example). Old school RAID tends to think of "like items" with stripes and parity... and in today's world, there's plenty of reliable, redundant storage systems that don't fit the traditional definition at all.

But my main point is simply not to assume what is meant by JBOD.
 

Master_shake_

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jbod.png


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Controller just takes a bunch of drives lays them end to end and then presents it as a volume to the OS.
 

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Master_shake_

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Does Highpoint make SATA products? I'm a Joe Average home user, with only SATA drives. The website seemed to show only SAS-based products.
Mines a 2720sgl which is a sas raid card.

The only difference is i'm using sas forward breakout cables.

SAS is compatible with sata.
 
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x509

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Mines a 2720sgl which is a sas raid card.

The only difference is i'm using sas forward breakout cables.

SAS is compatible with sata.
Master_shake_ What are "sas forward" cables? I have been building my own systems for like 30 years now, but that term is new to me? Are these cables different than regular SATA data cables?
 

Master_shake_

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Master_shake_ What are "sas forward" cables? I have been building my own systems for like 30 years now, but that term is new to me? Are these cables different than regular SATA data cables?
They go from a sas connector to sata cables.

The opposite cables, sas reverse breakout cables go from sata ports to sas connectors

They are not interchangeable.
 
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Ready4Dis

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As mentioned, JBOD is just a bunch of disks.... It doesn't mean they have to be arranged into an array. Just because you can and someone still calls it a JBOD, doesn't make it different. If you put it into a concatenated array, then that's fine, but it's not mandatory for JBOD (and I would even go so far to argue it's no longer JBOD but an array at that point). It's now a single interface/array for a bunch of disks, rather than just a bunch of disks. Terminology.is not always used correctly and as mentioned tends to change over time. This being said, if you plan to use it know what your looking for and how you are expecting the drives to work before buying hardware.
 

lopoetve

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Adding to Ready4Dis - It's literally a way of connecting a bunch of unrelated drives to a system. what the system does with it then is entirely up to the hardware/software it is connected to - it's effectively just a connection device. You can software RAID, hardware RAID, SDS, etc from there - however you want. In and of itself though, it's just like connecting a bunch of individual drives to your system.
 

x509

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Adding to Ready4Dis - It's literally a way of connecting a bunch of unrelated drives to a system. what the system does with it then is entirely up to the hardware/software it is connected to - it's effectively just a connection device. You can software RAID, hardware RAID, SDS, etc from there - however you want. In and of itself though, it's just like connecting a bunch of individual drives to your system.
Thank you to lopoetve and Ready4Dis for their replies.
 
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