Single Drive Stripe, then added 2 drives as Mirror -- whats my current zvol?

[Chirag K]

Hello
OK, I read through https://forums.freenas.org/index.ph...ning-vdev-zpool-zil-and-l2arc-for-noobs.7775/
but still not clear...

I am on FreeNAS 9.3
I had a Single Hard Disk volume. (1TB disk)

I just purchased 2 5TB disks. My plan was to create it as a separate volume as Mirror. But while exploring, I was able to extend the existing volume (1TB) by adding the 2 new 5TB disks.

Now I have 1 Volume with 5.4 TB size.. So somehow, the 1 TB was mirrored (giving me 500GB usable).
So now, I have a 3 Disk Mirror... Coming from hardware RAID, I am not clear on how this is handled behind the scenes.
Does FreeNAS proportionally distribute data and mirror data across 3 drives now?

I am just trying to get my head around it... What happens if my volume is over 4 TB Filled and one of the 5TB disk fails?

In hardware RAID, this would not work, but in software RAID its allowing so I am just trying to make sure I understand whats happening under the cover..

Please explain (I am technical so no worries if you go techie)

 

[Stux]

Can you post the output of 'zpool status'

 

[Chirag K]

FYI, I did not change the pool name from "hdd1tb"...

Code:

[root@freenas] ~# zpool status
  pool: freenas-boot
state: ONLINE
  scan: none requested
config:

        NAME        STATE     READ WRITE CKSUM
        freenas-boot  ONLINE       0     0     0
          da0p2     ONLINE       0     0     0

errors: No known data errors

  pool: hdd1tb
state: ONLINE
  scan: none requested
config:

        NAME                                            STATE     READ WRITE CKSUM
        hdd1tb                                          ONLINE       0     0     0
          gptid/256aefc6-f6e9-11e6-b876-848f69dd225c    ONLINE       0     0     0
          mirror-2                                      ONLINE       0     0     0
            gptid/d4eb252a-f8ba-11e6-ae06-848f69dd225c  ONLINE       0     0     0
            gptid/d629a590-f8ba-11e6-ae06-848f69dd225c  ONLINE       0     0     0
        logs
          gptid/261c2772-f6e9-11e6-b876-848f69dd225c    ONLINE       0     0     0
        cache
          gptid/2656eb93-f6e9-11e6-b876-848f69dd225c    ONLINE       0     0     0

errors: No known data errors
[root@freenas] ~#

 

[Stux]

Okay. You have a pool consisting of a 1TB drive (Ie a stripe with no redundancy) and a 5TB mirror

I would suggest fixing this. You can't remove a vdev, which leaves adding another 1TB to the first vdev, or backing up, rebuilding and restoring.

If you can't backup, I would suggest offlining one of the 5TB drives. Wiping it. Making it into a NEW pool, the replicating from your old pool to this new pool.

Then erase/detach/wipe the old pool.

Then add the 5TB as a mirror of the other 5TB (the one forming your new pool).

(This last step requires command line kungfu )

You will then have a 5TB mirrored pool.

Alternatively add another drive to the 1TB to make it a mirror instead of a stripe. Again, command line Kung fu)

 

[Chirag K]

Cool thanks!
i will work on this tonight...