Can I strip a vDev across two chassis?

[TidalWave]

SC847BE2C-R1K23LPB | 4U | Chassis | Products | Supermicro

847BE2C-R1K23LPB

www.supermicro.com

SC846BE2C-R1K03JBOD | 4U | Chassis | Products | Supermicro

846BE2C-R1K03JBOD

www.supermicro.com

Hey guys,

I inherited a Freenas server with 250TB of 6TB drives in 3 or 4 RAIDz2 configurations. Somehow there are still 18 available slots on these super micro chassis (the links above are not the exact models).

So i have 3x 15 6TB HDDs in RAIDz2 configurations stripped into on big zpool. Everything is great, but I need to add more storage. So I have 14 drive slots below and 4 drive slots available on the above chassis.

Remember the bottom chassis is a JBOD only. The two chassis are linked via a SAS cable.

So I want to add 15x 16TB HDDs for my new vdev. I know that the bigger size of 16 TB drives over the 6TB drive mixture is not recommended, but I'm not that concerned with performance, as I just need a lot more storage capacity.

I know that mixing vdev sizes of number of drives will no longer work using the expand fucntion in the GUI with the newer version of Freenas but I have been able to add different vdev storage sizes as long as all the HDDs in the vdev are the same size and the vDev itself matches the other vdev configurations as far as RAID level and number of drives.

So now onto my question:

Can i make a vDev with 14 drives on the bottom JBOD and 1 Drive on the top supermicro chassis? Since the software is not aware of the physical difference I'm sure it will allow me to, but will this configuration cause any problems?

I'd much rather have each vdev within it's own respective chassis, but for some reason, somehow, i have 14 slots on the bottom available and 4 slows on the top available. That's just the way it is mathmatically. I need more space, and making a single 14 drive vdev won't work because I need the actual datasets that are already created to be increased, not just a storage pool for a new dataset!

-Tidal

 

[sretalla]

All directly attached SAS/SATA drives are equal in the eyes of the OS, so you can stripe or combine any disk into any VDEV.

Clearly the potential for problems exists if you disconnect the chassis from each other, but I guess you're not planning to do that (including both being powered on all the time together).