Setting up v-dev's

[sewerman1]

I recently build a nas with 6 hdd's that are 4 tb each. My dilemma is:
Should i make 1 v-dev's of 6?
Should i make 2 v-dev's of 3?
Should i make 3 v-dev's of 2? (mirrored)
I want to expand in the future and 6 at a time is too much.

 

[BigDave]

This zfs based calculator will be of some help to you.
https://jsfiddle.net/Biduleohm/paq5u7z5/1/embedded/result/

Research the auto expand capability of FreeBSD/FreeNAS,
this is what I used to add space in my server;

Started with 6 - 3 TB drives in RAIDz2 and began to replace
one drive at a time as money allowed, then when you have replaced the last drive of the original six (I used 4TB drives),
the volume automagically expanded the usable space.

The benefit of this process is that when this process is complete, the original six drives are free now to use as you please. I made
a second volume and moved all 12 drives into a 16 bay rackmount
chassis.

 

[Robert Trevellyan]

Should i make 1 v-dev's of 6?
Should i make 2 v-dev's of 3?
Should i make 3 v-dev's of 2? (mirrored)

I would pick the first (in RAIDZ2) or the last. The middle option seems like the worst compromise.