2TB + 256GB = 1.1TB?

[AndrewSatellite]

Hi all.

 

I am new to unRAID and a bit hesitant to ask, but I am curious as to why I can't seem to add.

 

I am pretty sure if I add 2x 1TB and 1x 256GB into a single cache pool, I would total 2.256TB + - of storage.

unRAID seems to think it creates 1.1TB. I am sure i have only pooled it and not used any parity or other features, but I just can't be sure.

 

 

Have made some unbelievably embarrassing mistake? 

 

Kind regards,

 

Andrew

 

[JorgeB]

It's a btrfs limitation:

 

https://lime-technology.com/forums/topic/46802-faq-for-unraid-v6/?do=findComment&comment=480420

 

[NewDisplayName]

(u dont want to add them all as cache) so more space can be used.

 

Like 1 cache device (best is ssd)

and rest in array.

 

"Standard" Config would be like this:

1x cache (e.g. SSD) - for fast writing to array

1x parity (so if one drive of the array fail, u wont loose anything)

and as much array drives as u want/have/need

Edited March 8, 2018 by nuhll

[trurl]

You have to use btrfs raid0 if you want the full capacity with no redundancy. 

[JorgeB]

15 minutes ago, trurl said:

You have to use btrfs raid0 if you want the full capacity with no redundancy. 

Actually, single profile, raid0 will result in 512GB (256 + 256), only the single profile can use the full 1.25TB.

[trurl]

1 hour ago, johnnie.black said:

Actually, single profile, raid0 will result in 512GB (256 + 256), only the single profile can use the full 1.25TB.

He has 3 disks adding to 2.25.  That would be single as well?

[JorgeB]

8 minutes ago, trurl said:

He has 3 disks adding to 2.25.  That would be single as well?

Read to fast, though it was 1 + 256, in this case 1.1TB for raid1 is correct, raid0 should use all the space.