No Raid 10 option

[kappclark]

I have 4 disks (4x1 TB) which I was planning to set up as raid 10...Is this just terminology ? I spent some time lookig through forums, and this seems like it is not an option ..

I only see the Raidz2 option, but it doesn't seem the same as Raid 10 ... It doesn't really matter to me - I am looking for resilience and redundancy (I also will be using external backup, as I understand Raid is not a backup strategy) ..

I went ahead and chose the Raidz2 option (for 1.82 TB useable storage. Just looking for clarification, bcause it seems you can setup a raid10 array in ZFS,

Thank you for any help/clarification you can give..

 

[rvassar]

Create a pool with two mirror vdev's. That's a ZFS equivalent.

Ends up looking like this:

Code:

  pool: Example_Pool
 state: ONLINE
  scan: scrub repaired 0 in 0 days 05:46:14 with 0 errors on Wed Oct 16 05:46:15 2019
config:

    NAME                                            STATE     READ WRITE CKSUM
    Example_Pool                                      ONLINE       0     0     0
      mirror-0                                      ONLINE       0     0     0
        gptid/9da23931-847e-11e9-bcfd-002590a49227  ONLINE       0     0     0
        gptid/a435b481-7d9e-11e9-be7b-002590a49227  ONLINE       0     0     0
      mirror-1                                      ONLINE       0     0     0
        gptid/df5d8d95-4f2d-11e8-bc39-5cf9dd7211d0  ONLINE       0     0     0
        gptid/dfffbb0e-4f2d-11e8-bc39-5cf9dd7211d0  ONLINE       0     0     0

errors: No known data errors

 

[kappclark]

Thank you for the reply -- I guess I still have the FreeNAS training wheels on ...
I destroyed the raidz setup, and created 2 mirrors

Now I am not sure how to use the GUI to create the striping of the 2 mirrirs ...

 

[kappclark]

OK - did some digging, and saw you can extend an existing mirror ... I now have 1 pool (zmir-1) listing 2 mirrors underneath...

 

[tfran1990]

Looks right to me.

 

[recki]

Hi,

whats the reason for Raid 10? You lose 50% of the Diskspace.

regards ré

 

[rvassar]

Hi,

whats the reason for Raid 10? You lose 50% of the Diskspace.

regards ré

Speed. Read events can go to either mirror half, and ZFS will round-robin between the vdev's. So for a read heavy application you get potentially 4x the performance. Write, will be 2x, as they have to issue to each mirror half. But consider, in a RAIDz config, when you write all the drives in the vdev must complete before the transaction is done. In effect the same speed as a single disk.

 

[recki]

Hi,

ok i dont think abount the Performance, i only see the 50% Spaceloss.

regards ré

 

[kappclark]

So far, so good - many thanks for the guidance ... and I know the price that is paid for RAID .. I suppose Raid-z2 has the same 50% 'overhead' ...

but, considering that the wonderful FreeNas SW cost exactly $0.00, I am happy to go with this setup ...

 

[tfran1990]

I suppose Raid-z2 has the same 50% 'overhead' ...

No. it all depends on the amount of discs and capacity's along with the amount of vdevs in the pool.
It might have been a better move to know what all freenas can provide as far as storage options before choosing.

 

[kappclark]

THX for input --
Very pleased so far with this setup ... Migrated music library to NFS share and it is blazingly fast --