raidz/2

[SLIMaxPower]

After much ridicule from the community I am moving to raidz/2 and need advice.

I will be using a N54l 16gb ecc ram

This unit will have 7x3tb green HD and and can add an 8th (max) for spare.

5 drives for data and 3 spares ?

When the drives need upgrading is it just a matter of pulling out and reslivering ?

The second unit is a n40l 16gb ecc ram.

This unit will have 6x3tb green HD and 2tb green for jails.

4 drives for data and 2 spares ?

Lastly my ups will connect to the n54l. How will I set both servers to shutdown if power is lost.

cheers

 

[danb35]

Well, RAIDZ2 would have two parity disks, so if you have 8 disks total in a RAIDZ2 vdev, there would be six data and two parity*, for a net capacity of about 18 TB. None of these disks would be "spares"; they'd all be used in the array. FreeNAS does not support automatically activating hot spares when a disk fails. To replace a disk in an array, just follow the click-by-click instructions in the manual.

* RAIDZ doesn't use dedicated parity disks; the parity is spread out across all the disks in the array. However, the parity consumes space equal to two disks in RAIDZ2.

 

[cyberjock]

What danb35 said. There's a difference between parity and spares. Do not confuse the terminology because they mean *totally* different things. ;)