Understanding Pools and Sizing

[palakmar]

Good Evening, I am fairly new to freenas/truenas and originally when I set up a pool I used all drives. I am curious, is it possible to reduce the size so that I can create an additional pool or two?

 

[Nick2253]

The short answer is no, but it really depends on what you're trying to do.

First off, I'm guessing that you should check out the primer on ZFS: https://www.truenas.com/community/resources/introduction-to-zfs.111/

In a nutshell, a ZFS pool is a collection of vdevs, and each vdev is a collection of one or more drives. When you have multiple vdevs in a pool, data is striped across the vdevs. Each pool can have one or more datasets.

Which brings us to the real question: why do you want multiple pools?

From a performance perspective, one pool is almost always better. If you are trying to segregate your data, you want to use datasets, not pools. If you're trying to increase your hard drive redundancy, you want to change how your vdevs are configured.

If you want a really detailed answer, it really helps to include your hardware, as well as whatever you are trying to accomplish with that hardware.