Used SAS or new SATA NAS disks ???

[poldas]

I can buy used disks SAS 7200 rpm 2TB ST2000NM0023 (100$) or new SATA Seagate or WD dedicated for NAS. Which are better for FreeNAS used SAS or new SATA?

 

[HoneyBadger]

ZFS will work fine with either - the question is down to "which do you need?"

Give us an idea of what your end goal is with the system, such as the hardware specs, a desired pool config, what you'll be serving from it, how many hosts/clients accessing it at once, what protocols, etc.

 

[Ericloewe]

100 bucks for 2 TB seems like a crappy deal to me for a new drive, much less a used one.

 

[Chris Moore]

I can buy used disks SAS 7200 rpm 2TB ST2000NM0023 (100$)

That is far too much to pay for used disks at that capacity. Those are 2TB drives and (in the US) are selling between $25 and $50 depending on market pressure.
https://www.ebay.com/itm/ST2000NM00...3-2TB-7-2K-6G-LFF-SAS-HARD-DRIVE/263739479473
They are decent enough drives. I have a server at work running those where 10 of them are still going after 6.2 years of power on hours.
The thing about it is, at that price, you may as well buy new SATA drives instead. You should not expect a used (old) drive to be better than a new drive.
As an example:
https://www.newegg.com/Product/Product.aspx?Item=N82E16822179007