I am brand new and confused.

[jbtree69]

I have 3 22tb drives and i want a raid 5 config. I also have 5 2tb drives I wanna do in a raid 5. And i also have 2 2tb m.2 for cache drives.  I have been reading thru the forums and I tell you I am more confused now then ever. Can I set 1 22tb as parity for one pool/array(whatever its called) and 1 2tb as parity for the other pool/array? I have always used windows with raid and this was a lot easier, however everone tells me to try Unraid that it will change my world. so far just a headache. Anyone offer some help or info would be great.

[MAM59]

Keep cool...

Currently there is a "naming problem".

"ARRAY" usually means in Unraid that there are some independent Data Disk an one (or two) Parity disks that ensure data integrity and allow restauration if one drive (or two) fails.

This is NOT RAID5!!! (thanks alot!)

 

Since the newest release there is now also the zfs filesystem available which allows arrays (the naming problem!) with several different raid levels.

Some even tried to use a ZFS Array within the UNRAID array (this works but is totally nonsens and slow as a dog! AVOID AVOID AVOID!!!).

 

To work UNRAID currently needs one UNRAID array (and ONLY ONE!) and a lot of "pools". A ZFS Array (RAIDZ called now) can form such a pool.

 

The main advantage of the UNRAID array is that you do not need all the same drives to form it up. The only restriction is that the parity drive needs to be the largest one of all all the time (you can only add larger data disks AFTER you have swapped the parity drives to at least that level). And, even if you break up the array someday, the single disks are still accessible and contain all the data. The main disadvantage is that currently there is no read cache. You can add ssds or nvmes as "cache" but they will be only used for writing new files. And after a "mover" has moved the data to the main array and freed the cache again, read and write speed will drop down to drive's speed (writes even slower because parity needs to be kept in sync)

 

ZFS comes with all the "nice to have" features of modern filesystem including snapshots, a read cache in ram and so on. But it still uses strict RAID which means you have to use the same drives (at least the same size) for ALL disks and there is no way to enlarge them later on. And, of course, if the array fails miserably all data is lost including the files that are on the still healthy drives.

 

So this is more or less a descion you have to do yourself, flexibility and safety vs speed and "bound to current state".

 

You could set up an UNRAID array with your 3 22Tb drives (using one as Parity) and a ZFS raid5 pool with the remaining 2Tb drives (but really, I would look at the electricity bill and throw them away and  add another new 22tb one to the main array).

 

The main clue about UNRAID is that it is NOT RAID!!!

 

[bmartino1]

You can always start over including keeping parts of the config.

By going to tools new config:



unraid is linux and linux uses software raid technology example mdadm and unraid uses a party raid based on # of drives and its configurations

Unraid needs 1 disk to be in the array to use the system. Please see docs:
https://docs.unraid.net/unraid-os/manual/storage-management/

then you can make your pool of disk in resemblance of a raid 5 in your case I would recommend a zfs file system and use raidz1 for the 3x 22TB

Step 1 ignore disk setup and install the plugins you need first:

I recommend you install:

 

and both the zfs plugins:

 

optional but recommended:

to manage and see btrfs/zfs snapshots:

The ideal setup is pair 2 drives:

 

By default, the array format prioritizes xfs
by default, pool Priorities btrfs by default.

To set and change you would click on the name in my case I added a 3 disk pool named it and added disk then click on vm-zfs to tell its file type to be zfs raidz1
*Be sure to set your file system types to use zfs...

You can plug in another usb drive to be used as disk 1 of the array to meet the bare min. Then have all disk added as separate pools.

This way you can add a raid 5 type configuration. Or you can use the array as intended and have a Disk 1 with 2 party
the parity is essentially a Linux accessible drive that mirrors the data on the disk it parity.

You can have a disk 1 and disk 2 be parity to a bigger disk, and they would share parity as an example.

In your case, I would use the 2x nvme as disk 1 and cached

then add 2 pool devise 
3x 22TB 1 pool zfs raidz1 (which in essence is a raid 5 type configuration that and keep working with losing 1 disk
5x 2tb  2nd pool as zfs raid z2 (which is also in essence a raid 5) that can keep going if 2 disk are dropped from the array.

https://www.45drives.com/community/articles/RAID-and-RAIDZ/#:~:text=RAID5 protect your data against,parity and striping RAID levels.

 

raid z1 is striping parity and mirrored which is the desired result to maximize space and speed of the data on the pool.
https://www.raidz-calculator.com/raidz-types-reference.aspx

Edited May 5 by bmartino1
I can't type today...