Hello all 
i go receive an old pc, not so old, and i already have the 2 wd 4to hardrives and a 250go ssd for.
I watched at a video for it and the youtuber done the pool with two disks in pool but as i know raid1 is preferable ?
Thx a lot !
YoG
Raid-Z1 needs three drives. Your only choice is a mirror pair if you only have two drives and want some redundancy.
OK thx a lot.
Have a good d’Ay ^^
Note that your title asks about “Raid1,” while Barky’s answer mentions “Raid-Z1.” The Z is critical. RAID1 in conventional RAID nomenclature is a mirror; RAIDZ1 is comparable to RAID5 in traditional RAID levels.
Okok i understand. Due to m’y lessons of network, i thought raid1 was possible but so let’s go to mirror.
RAID1 and mirror are the same. RAIDZ1 is something different.
OK thanx in fact i thought raid1 was possible.
Thx a lot.
RAID1 is possible. It’s a mirror. How many more times do you need to read this?
It’s a language barrier thing I think. Their using translate or something.
OK sorry. Thx