Mixing disks of different sizes in a VDEV is not allowed.

[ztx]

I'm the first time to install a freenas server, I have 4TB*3 and 8TB*3 disks, I want to pool using all 6 disks in raidz2, and update 4TB disks to 8TB later, but when creating pools in the GUI, It says "Mixing disks of different sizes in a VDEV is not allowed. " and the create button is grayed out.

Is there a way to create a pool using all 6 disks in 1 vdev?

 

[Tigersharke]

I am not an expert with FreeNAS so my question is pointed toward those who are more familiar:

Is there any difference whether this user attaches the smaller drives first?

I know that outside of FreeNAS, ZFS would permit such a setup as desired, so I am curious how or why this is disabled in FreeNAS. My guess is that it might see the large disk first and instead of defaulting them to match the smaller ones, it simply "fails" so doing the reverse seems more likely to succeed. I have not tried anything like this on my own FreeBSD box but I do have raidz2 with a few more drives. :)

 

[ztx]

Thanks for reply.
It's my fault. When making boot disk, I selected the 11.3 beta, reinstall with 11.2-U7 created the pool successfully.

 

[Tigersharke]

Thanks for reply.
It's my fault. When making boot disk, I selected the 11.3 beta, reinstall with 11.2-U7 created the pool successfully.

Glad to hear of your success. There must be some reason why it is changed in 11.3 beta, perhaps that configuration needs further testing with regard to newer ZFS capabilities. *shrugs*

 

[ztx]

I copy a 35gb iso file to freenas, got 27mb/s, it's very slow. before I puchased the 8tb disks, I create a 3*4tb raidz and got more than 100mb/s.

Is this speed normal?

 

[ztx]

Reboot system, get a 100MB copy speed.:)

 

[danb35]

There must be some reason why it is changed in 11.3 beta

I expect it's simply to keep users from implementing suboptimal pool configurations. Such things have been there for quite some time, though there's historically been a "manual setup" button that lets you create whatever crazy configuration you want. If that's gone away, that would be a bad thing, because sometimes people have good reasons to do apparently-stupid things.

 

[Arwen]

Yes, we need an "expert" mode. For exactly the reason the orginal poster stated: Will replace the smaller sized disks later.

This does bring up an interesting thought. Does ZFS do the copy on write to the full 8TB disk? Not going above the total of 4TB used limit imposed by the RAID-Zx, (in this example). For spinning rust, I guess it does not mater. But, for SSDs it would matter.

 

[Tigersharke]

I understand the reasoning (if it is *intentionally* denied) and I'm sure it causes the best experience/performance for the most users. However, even if there is an obscure(d) setting to "permit less than optimal configuration" or whatever, it may be preferable to denying entirely. The simple reason being that if ZFS permits something, it ought to be possible with FreeNAS as well. Failing that, if FreeBSD can create a sub-optimal arrangement and FreeNAS could "import" it, that would be another compromise that would work for those expert users. In the second case, perhaps even a bootstrap might be nice, that is to start with a FreeBSD install which is configured (ZFS vdevs/pools as desired) and then FreeNAS is directly installed over it by way of a script (bootstrap) which is suited for that situation. OPNsense had such a system prior to switching to HardenedBSD as their base and it worked rather slick but no ZFS yet.

 

[melloa]

Just installed a fresh 11.3 to test, had 6x300GB and one 900GB and was planning to replace the 300s with 900s later ... couldn't create my pool. I guess could do it from the shell, but didn't want to try as I had another 300GB available, so create the pool and replaced one of the disks ...

If it's gone, we need the option to create the pool with different disks' sizes. A not recommended warning in bold red, but let the user continue with the stupidity - some times, like this time, there is a good reason.

 

[Arwen]

@melloa, If it's stupid but works, it's not stupid. The problem arises when someone does this without thinking. Like making a pool out of 5 x 4TB disks & 1 x 1TB SSD. Then both wonder why they don't have enough space, and then figure out how to backup all that is used to re-do the pool. (In that example, they may have intended to use the 1TB SSD for jails, warden, VMs, etc... just never got A Round Tuit.)

As you point out, there are multiple good reasons to do this. Having both an expert mode, and not recommended warning would be acceptable.

 

[melloa]

If it's stupid but works

I've added me to that category ;)

Having both an expert mode, and not recommended warning would be acceptable.

Ditto!

 

[Espen_^]

Same here.

 

[Espen_^]

I cant find the edit post buttn so i make a followup.
I can use the two 500gb disks to make a vdev but not the 250gb's. I destroyed the 500 pool and tried to make one from the 250's but no go.

 

[Patrick M. Hausen]

As you point out, there are multiple good reasons to do this. Having both an expert mode, and not recommended warning would be acceptable.

While I agree with your reasoning I'd like to point out: the expert mode is already there. It's called "command line". Just create your pool to your heart's content, then export from CLI, import from UI. Done. See my post about sharing disks for boot and data pool, for example:

HOWTO: setup a pair of larger SSDs for boot pool and data

Moderator Warning: This HOWTO will damage the ability of your TrueNAS appliance to properly maintain itself, will break the ability to replace failed drives, and may cause problems with upgrades and updates. TrueNAS is not designed to do this sort of partitioning, and the developers are not...

www.ixsystems.com

Patrick

 

[melloa]

the expert mode is already there.

Correct, for me, you, and others to use, but than I'd be going back to my FreeBSD server install without GUI, like I had before. Not a problem for me. The point of using FreeNAS is to make things simple, easy. Features are requested all the time and this one was there on previous version.

 

[Scharbag]

Is this actually the case that 11.3 will not allow you to create a vDev of different sized disks?

 

[artlessknave]

Is this actually the case that 11.3 will not allow you to create a vDev of different sized disks?

yes.
its massively annoying for insufficient reason. I see it myself, and other people have created posts because 2 drives that says they are identical are somehow not and the GUI tells them to go away.
(I am a huge fan of "yes i know now do it anyway" buttons, even if it takes 3 confirmations w/e.)

 

[cobrakiller58]

Is this actually the case that 11.3 will not allow you to create a vDev of different sized disks?

Yes iX out right blocked it in the GUI they appear to be have fixed this mistake in the 11.3u2 release that is coming at the end of the month

https://jira.ixsystems.com/browse/NAS-105051

 

[KenwoodFox]

Yes iX out right blocked it in the GUI they appear to be have fixed this mistake in the 11.3u2 release that is coming at the end of the month

https://jira.ixsystems.com/browse/NAS-105051

Thanks for the link!