Create raid with different size HDD

[jonbrockway]

I have Terramaster F4-422 NAS
I have a ironwolf 4tb drive set up as a single disk - with Data on it
I also have an ironwolf 8tb drive set up as a singe disk -
I have installed the 8tb drive but there was no option to create raid when i installed it?
Is there a way to create a raid with these?
if so how?

[TMRyan]

Hello,
Did you add an 8T hard drive? Do you want to combine two 8T into Raid 1?

[Charlie_Croker]

So you have a 4TB and have added a single 8TB drive and now have two drives installed? But they’re different capacities.
RAID 0 and RAID 1 need both drives to be same capacity.
RAID 5 needs a minimum of 3 drives
RAID 10 needs 4 drives
So unless you’re willing to lose 4TB from your 8TB you will get no benefit.
You could use spanning which makes the drives appear as one 12 TB drive but the risk is you have doubled the chance of losing data due to a drive failure and got no speed increase.

But if you have now added a second 8TB drive (your question isn’t completely clear), then you can RAID both the same 8TB drives into RAID 0 for increased speed or RAID 1 for resilience. (Technically RAID 1 isn’t a backup, )https://getprostorage.com/blog/understa ... d-storage/

[jonbrockway]

Thank you so much. Obviously I'm a total newbie sorry haha
Right now I have 2 HDD ( 1 is a 4tb HDD and the other is an 8tb HDD )
It sounds like best case is having 3 of the same sized HDD in order to create RAID 5 - correct?
Would it be possible for me RAID 5:
2 X 4tb HDD ( I would need to purchase another 4tb HDD )
1 X 8tb HDD (I assume I lose some capacity on the 8tb HDD - it would be reduced to 4tb?)
I'm just trying t make sure my data is backed up somehow
I have family pictures and huge CD collection that I just ripped so want to make sure I have backup in case there is an issue.

[Hardfecx]

For a Raid5, you need 3 x 4TB HDD, and you can use your 8TB as second Backup of your Raid5 when installing it per USB

[Spaniard]

When they say "disks" they mean partitions.
The smallest hard disk will determine the size of those partitions.
So you can have 2x4TB partitions in your 8TB disk and use 1 partition to be "paired" in RAID 1 with the 4TB partition of the 4TB disk and use the second partition of the 8TB disk for something else.

Keep in mind these type of combinations may have an impact on the transfer speeds depending on the simultaneous use of the different partitions.