Difference Between Traditional RAID vs ZFS RAIDZ?

[Thien Thy]

Hello everyone,
I have just setup a RAID 10 on my PC with six 4TB WD RED NAS drives (24TB total with 10.9TB usable space). Originally I wanted to setup RAID 5 but after researching and limitation on the LSI HBA 9211 doesn't have RAID5, I set up RAID 10.

Now I want to create a new box using FreeNAS using the same size drives of 4TB WD RED NAS to get the same amount of usable storage space (10TB or more).

The purpose is to share files to family members with some sort of safety

Goal in order of importance:
1. Speed
2. Redundancy
3. Capacity <= well, this is all depending on how many drives I actually will throw at it right?

I have done some reading at this forum and doing some Google search to find out the similarities to understand which RAIDZ should I use.

Please give advice.

Traditional Raid vs. ZFS RAIDZ
RAID 0 =>
RAID 1 =>
RAID 5 => RAIDZ1
RAID 6 => RAIDZ2
RAID 10 => Nested VDEV

Thank you.

 

[Bidule0hm]

To complete a bit:

RAID 0 => Striped drives
RAID 1 => Mirror
RAID 5 => RAIDZ1
RAID 6 => RAIDZ2
RAID 10 => Striped mirrors

 

[Nick2253]

You gave us your priorities, but you didn't really give us your requirements.

From one point of view, speed is really easy. Pretty much anything you set up nowadays will saturate a 1Gb link. If you require 10Gb or more, then you'll have to work harder on your system.

Since redundancy is the next most important, I'd recommend RAIDZ2 or RAIDZ3. A six-drive RAIDZ2 vdev is pretty common around here, and will give you both lots of speed and lots of capacity.

Which brings us to capacity. 6 4TB drives in RAIDZ2 will give you about 14.5 TiB of usable space.

In other words, assuming you're a pretty average user around here, six drives in RAIDZ2 will more than meet your need.

 

[solarisguy]

Expanding on Guru's words:
* RAID 0 => Striped drives => zpool create storage_name devices
* RAID 1 => Mirror => zpool create storage_name mirror devices
* RAID 5 => RAIDZ1 => zpool create storage_name raidz devices
* RAID 6 => RAIDZ2 => zpool create storage_name raidz2 devices
* RAID 10 => Striped mirrors => zpool create storage_name vdev1 vdev2 # vdev1 and vde2 are mirrors created earlier, it can be accomplished in one line too

RAIDZ3 => zpool create storage_name raidz3 devices

Other RAID levels are possible, too.

P.S. You would do the above if you were not running FreeNAS, but FreeBSD or another operating system. FreeNAS is an appliance, and storage setup is done using GUI. FreeNAS GUI may not offer the same complexity level as the command line (but a chance of an instant failure is reduced...).

 

[Thien Thy]

You gave us your priorities, but you didn't really give us your requirements.

From one point of view, speed is really easy. Pretty much anything you set up nowadays will saturate a 1Gb link. If you require 10Gb or more, then you'll have to work harder on your system.

Since redundancy is the next most important, I'd recommend RAIDZ2 or RAIDZ3. A six-drive RAIDZ2 vdev is pretty common around here, and will give you both lots of speed and lots of capacity.

Which brings us to capacity. 6 4TB drives in RAIDZ2 will give you about 14.5 TiB of usable space.

In other words, assuming you're a pretty average user around here, six drives in RAIDZ2 will more than meet your need.

Yes, since my PC RAID 10 has 10.9 TiB, I would like to have at least the same 10 TiB or more usable space. I probably wouldn't need anything more than 15TiB but...who know how much I shoot photos and videos in high quality :)
I really like the 14TiB from RAIDZ2 by using the same number of 6 4TB drives if the Reading speed isn't much of the issue.

Thank you.
Thy

 

[solarisguy]

[...] I really like the 14TiB from RAIDZ2 by using the same number of 6 4TB drives if the Reading speed isn't much of the issue.

Thank you.
Thy

What is your desired reading speed (or performance in general)? With a standard setup (and recommended hardware), a Gigabit Ethernet link would be saturated.

As long as you understand that you should attempt to not store more than 12TiB of files in 14TiB available, you would be perfectly fine.

P.S.
You can use your 9211, but you would need to flash it from IR to IT mode.