Just a random question?

[WelshDdraig]

I have been thinking of this question for a while, but not having the hardware has prevented me from trying it. 

 

I know it sounds stupid, totally impractical, and should never be done for storage due to the un-reliability. 

 

Can you Raid 0 a Raid 0. 

 

An example being, 2 3TB drives in one Raid 0 and 2 more 3TB drives in another Raid 0. Can you then Raid those two Raid Arrays together?

 

It's completely throwing what RAID is out the window as Raid is all about redundancy, hence the R. I was just wandering If it is possible and what performance you would get if using SSD's.

[Tedster]

AGH!

 

I don't see how you'd manage the second layer of raid. If you could somehow set it up it would definitely work.

 

If you had 2 raid cards raid 0'ing as one disk per card, then you could probably do it I suppose.

[Guest]

You can raid all of them same array and in raid 0 and you will have better performance.

You cant add more layers.

 

basic raid0 with 2 discs:

     x

      |

 --------

 |        |

1       2

 

your idea:

                    y

                    |

       ----------------------

      |                          |

     x1                       x2

      |                          |

 --------                  --------

 |        |                 |        |

1       2                3       4

 

but by nature of how raid0 works your idea is converted to this:

 

 

              y

               |

 --------------------- 

 |        |        |        |

1       2        3       4

[soup]

 Raid is all about redundancy, hence the R.

Is RAID 0 a RAID?

Is that why it is 0  (there is NO redundancy)?

[WelshDdraig]

AGH!

 

I don't see how you'd manage the second layer of raid. If you could somehow set it up it would definitely work.

 

If you had 2 raid cards raid 0'ing as one disk per card, then you could probably do it I suppose.

As I said, I know it's stupid, but I don't know if its possible, lol. I don't want to try it. I'm just curious. I want to see someone try it.

[WelshDdraig]

Is RAID 0 a RAID?

Is that why it is 0  (there is NO redundancy)?

Technically no, but the R does stand for redundancy, or Redundant, I should say. So why does everyone call it a RAID 0 still. 

[WoodenMarker]

Technically no, but the R does stand for redundancy, or Redundant, I should say. So why does everyone call it a RAID 0 still. 

It's easier to associate disk arrays with RAID and calling it AID 0 sounds weird. 

[WelshDdraig]

It's easier to associate disk arrays with RAID and calling it AID 0 sounds weird. 

Thanks for clearing that up for me.

[Extingquish]

I've always wondered the same thing about a possible RAID 66 array...

[WelshDdraig]

You can raid all of them same array and in raid 0 and you will have better performance.

You cant add more layers.

 

basic raid0 with 2 discs:

     x

      |

 --------

 |        |

1       2

 

your idea:

                    y

                    |

       ----------------------

      |                          |

     x1                       x2

      |                          |

 --------                  --------

 |        |                 |        |

1       2                3       4

 

but by nature of how raid0 works your idea is converted to this:

 

 

              y

               |

 --------------------- 

 |        |        |        |

1       2        3       4

Nice explanation. 

[soup]

 So why does everyone call it a RAID 0 still. 

 

Maybe they use the zero to intimate that it is outwith the actual RAID canon?

[Captain_WD]

I have been thinking of this question for a while, but not having the hardware has prevented me from trying it. 

 

I know it sounds stupid, totally impractical, and should never be done for storage due to the un-reliability. 

 

Can you Raid 0 a Raid 0. 

 

An example being, 2 3TB drives in one Raid 0 and 2 more 3TB drives in another Raid 0. Can you then Raid those two Raid Arrays together?

 

It's completely throwing what RAID is out the window as Raid is all about redundancy, hence the R. I was just wandering If it is possible and what performance you would get if using SSD's.

 

Hey Alexp10v2,

 

What would you aim for by RAIDing two separate RAIDs? RAID 0 between 2 drives splits all data in two and evenly writes on both drives. Combining two RAID 0 setups would split the already split data in 2 more parts. That is pretty much what would happen if you put 4 drives in a single RAID 0 array. You can do a RAID 0 from two other RAID 0 setups but you would need either a separate RAID card for the second RAID or do it with software. Creating the two separate RAID levels would cause the speed to be slower compared to one whole 4-disk RAID 0 as the information would need to be processed twice (for the separation and distribution of the data.

Combinations like this exist in other types of RAID such as RAID 10, RAID 01, RAID 50, RAID 60, etc. where data is first given redundancy and then striped or vice versa.

 

RAID 0 is considered a RAID because it is still an array of drives, working together, appearing as one whole volume. The redundancy part does not exist with this type of RAID (maybe that's why they put it as a 0), but it still belongs to the category of array of drives, working together to for a single volume storage space.

 

Hope that clears it a bit,

 

Captain_WD.

 

PS: An easy and inexpensive way to experiment with RAID is to use flash drives with a USB hub.

[WelshDdraig]

 

Hey Alexp10v2,

 

What would you aim for by RAIDing two separate RAIDs? RAID 0 between 2 drives splits all data in two and evenly writes on both drives. Combining two RAID 0 setups would split the already split data in 2 more parts. That is pretty much what would happen if you put 4 drives in a single RAID 0 array. You can do a RAID 0 from two other RAID 0 setups but you would need either a separate RAID card for the second RAID or do it with software. Creating the two separate RAID levels would cause the speed to be slower compared to one whole 4-disk RAID 0 as the information would need to be processed twice (for the separation and distribution of the data.

Combinations like this exist in other types of RAID such as RAID 10, RAID 01, RAID 50, RAID 60, etc. where data is first given redundancy and then striped or vice versa.

 

RAID 0 is considered a RAID because it is still an array of drives, working together, appearing as one whole volume. The redundancy part does not exist with this type of RAID (maybe that's why they put it as a 0), but it still belongs to the category of array of drives, working together to for a single volume storage space.

 

Hope that clears it a bit,

 

Captain_WD.

 

PS: An easy way and inexpensive way to experiment with RAID is to use flash drives with a USB Hub

 

Thanks for the response.

 

I was just just curious to see if it was possible. I have no intention of doing it. It's just a question I have been thinking of. 

Thanks for also clarifying why people still associate a RAID 0 as a RAID. I knew the redundancy goes with a RAID 0 array, but I did not know why it was still called a RAID.

 

 

PS: An easy way and inexpensice way to experiment with RAID is to use flash drives with a USB Hub

Thanks for the idea about the USB drives. I never thought about doing it that way for experimentation. That's something for me to try when I get my desktop back.  

 

Thanks again. 

[Captain_WD]

Thanks for the response.

 

I was just just curious to see if it was possible. I have no intention of doing it. It's just a question I have been thinking of. 

Thanks for also clarifying why people still associate a RAID 0 as a RAID. I knew the redundancy goes with a RAID 0 array, but I did not know why it was still called a RAID.

 

Thanks for the idea about the USB drives. I never thought about doing it that way for experimentation. That's something for me to try when I get my desktop back.  

 

Thanks again. 

 

You are welcome RAID storage is a vast topic and IMHO has a lot of potential and we have yet to see stock RAID sollutions for both internal and external hard drives and SSDs. I tested the WD My Passport Pro and I have to say I am very impressed by what such a portable RAID solution offers. In case you are interested, here's a link: http://www.wdc.com/en/products/products.aspx?id=1240.

 

Feel free to ask if you have any other questions

 

Captain_WD.