Hi all,

I started using Unraid like two months ago and so far everything works fine. I added some more disks fast, so my first question:
When to add a second parity? Do I already have too much disks in, or should I be relaxed until a adding the disk number N to the array?

My actual setup:

• 1 Parity - 18 TB

• 4 Data - 18 TB (A 5th disk is already prepared)

• 2 Data - 12 TB

• 2 Data - 10 TB (Not yet installed but already prepared for)

Second Question: Is is possible to add a second array?

Background: have all my VMs and stuff running on a mirrored NVMe BTRFS Pool, which is fine but too small.
I will add a HighPoint Rocket 1180 HBA with 8 x 7,68 TB NVMe Disks to the Host, and I would want to use the same Unraid-Feature for them too.
And add a first backup of the data of the NVMes onto the spinning array each night.

Or should I create a ZFS Pool for that? I would love to have the best performance but also keeping some flexibility.

BR

Edited October 22, 2025Oct 22 by DatacenterGuy

With the number and size of the current disks, I would add a 2nd parity now. Of course, it also depends on how important the data is and if there are backups.

18 minutes ago, baron.sh said:

Second Question: Is is possible to add a second array?

Not yet, soon.

19 minutes ago, baron.sh said:

Or should I create a ZFS Pool for that?

For NVMe devices, I would recommend a ZFS pool—much better performance and TRIM support.

1 minute ago, JorgeB said:

For NVMe devices, I would recommend a ZFS pool—much better performance and TRIM support.

Thanks! So, for NVMe or SSD in general, it should be avoided to add them into the array, as they are not making use of TRIM support there?

Correct, any SSDs.