RAID 10 configuration help

[DSMDuDE]

Hello,
I'm pretty new to FreeNAS and learning it as I go along. During my searches I am having a hard time finding anything on how to properly setup RAID 10 environments. I'd like to use this in our production ESXi VMware environment.

Via a Youtube video I have configured the following, but it just does not seem correct:

Current FreeNAS setup with 18 4TB WD Reds

Thanks!
Nick Andersen

 

[Dice]

welcome onboard fella!
If you disregard everything you've "learned" from youtube and start from square one, you'll be fine.
Recommended newbie reads are linked in my signature. Read those. Reference the manual for clarification.
It will be the best invested time you'll have ever done with regards to your data integrity.

cheers

 

[DSMDuDE]

Thank you for the welcome and introduction information and I will look through it. I am finally posting because from my searching and reading I can not seem to find my answer. Yes, I have tried the Wizard setup selecting Virtualization which shows Raid 10, but nothing happens from there. The reason I linked the Youtube video is because it was really the only source of information I could find that showed maybe how it could be configured, but something just does not feel right and that lead me to this forum for help.

-Nick

 

[Arwen]

In ZFS terminology, a RAID-10 is called Mirrored vDevs, (virtual devices). Basically ZFS
takes disks, (like 2, but can be 3 or more to increase redundancy and read speed), and uses
them as a Mirror virtual device. To get more IOPS, (I/O Operations Per Second), you add
more vDevs, (Mirrored pairs).

VMs, (Virtual Machines), tend to like more IOPSs. So it's a general recommendation to use
several Mirrored vDevs for a ZFS pool layout when designing for VMs.

As for creating Mirrored vDevs from the FreeNAS GUI, sorry, I don't know. Most of my
experience with ZFS is command line with Solaris and Linux. Whence my FreeNAS was
setup, have not had to re-visit the disk layout in the GUI.

Last, in general, VMs prefer a SLOG on specific type of hardware. SLOGs on consumer
grade SSDs is not recommended. Without a SLOG, write performance can be spotty.

 

[Dice]

Uninstall "raid10" from your FreeNAS vocabulary.
As a systems engineer you probably are aware of importance of terminology to avoid confusion.
Here is how we do it:
https://forums.freenas.org/index.php?threads/terminology-and-abbreviations-primer.28174/

 

[danb35]

I have configured the following, but it just does not seem correct:

Both of your image links are broken, so we can't see what you have configured, or why you don't think it looks right. Here's what it should look like with four disks:

Repeat with additional rows for each pair of disks.

Edit: The method used in the video would work too, but it's a lot more steps for no reason.

 

[DSMDuDE]

Thanks for all of your replies. I have been doing some thinking and planning and wondering if I should just use RaidZ2. I am just curious if this is the best for a VMware production environment? What I am thinking is the following.

We have 18 4TB drives. I am thinking since RaidZ2 is a min of 4 drives and allows 2 to fail to do this:

I would be able to do 3 of these volumes

Thanks,
Nick

 

[danb35]

I have been doing some thinking and planning and wondering if I should just use RaidZ2. I am just curious if this is the best for a VMware production environment?

I wouldn't recommend it. Four-disk RAIDZ2 vdevs aren't going to be any more space-efficient than two pairs of mirrors striped together, and will only get you half the IOPS.

 

[Dice]

I have been doing some thinking and planning and wondering if I should just use RaidZ2. I am just curious if this is the best for a VMware production environment?

No.
You are significantly better off by running mirrors.

 

[DSMDuDE]

So, I should be good setting up my volumes like the following and assigning a spare drive for each volume. (I know i'll have to buy more) Having the spare as a failure.

 

[danb35]

So, I should be good setting up my volumes like the following and assigning a spare drive for each volume.

That would work. A dedicated spare for each four-disk volume might be a bit much. Do you need to have three separate volumes? Is there a reason you don't want a single 12-disk volume?

 

[DSMDuDE]

That would work. A dedicated spare for each four-disk volume might be a bit much. Do you need to have three separate volumes? Is there a reason you don't want a single 12-disk volume?

My thought is I am going to have multiple production clients running off of this FreeNAS. My thinking was multiple smaller volumes would be better instead of one large volume in a failure aspect, so in case one volume goes down it may take down 1-2 clients rather than all of them.

I am open to suggestions

 

[gpsguy]

As @Arwen already said "VMs, (Virtual Machines), tend to like more IOPSs. So it's a general recommendation to use several Mirrored vDevs for a ZFS pool layout when designing for VMs."

My thinking was multiple smaller volumes would be better instead of one large volume in a failure aspect, so in case one volume goes down it may take down 1-2 clients rather than all of them.

As a side note, if you're planning on using iSCSI, you should plan on keeping your usage under 50%.

For example, one of our expert users, built a system a couple of years ago that included 24x2TB drives (48GB raw). He configured the server for 8 sets of 3 way mirrors (16TB). If he stayed within the 50% rule, he wouldn't exceed 8TB. As I recall, he was using less than 4TB. He was looking for great performance. While home users might balk at a solution like this, it's cheap compared to what enterprises might pay to a storage vendor.

Do you currently have SAN/NAS storage as a backend to your ESXi servers? If so, what's your current setup? How's the performance?

What are you trying to achieve by going with FreeNAS? Eliminating the storage vendor with their hardware/software and yearly maintenance fees?

 

[Dice]

so in case one volume goes down it may take down 1-2 clients rather than all of them.

Additionally you would have to add a SLOG for each pool, and L2ARC for each pool. That would ramp up costs significantly for the machine.
If you end goal is to have say 12 HDDs,
I'd set them up in one pool, 5x vdev mirrors, 1 or 2 hot spares, a SLOG and L2ARC SSD.