ZFS Volume Question

[RDCLAN]

If you have a ZFS Volume setup and in use and its space becomes limited can expand it? System like Linux's LVM and Windows 8 Storage Spaces can do this without destroying the existing data.
I would like to know if FreeNAS can do this as well.

Any help would be very helpful. Thank you.

 

[david kennedy]

Yes, but only by adding another VDEV ideally of similiar redundancy.

Say you have "mypool" and it is 5 drives in raidz1 config.
To expand this you would need to add another vdev to the pool consisting of 5 drives in raid1.

Unlike in linux you cant reshape an array by adding single drives and you really should not mix redundancy levels in a pool.

 

[RDCLAN]

Thank you very much for the explanation, this help a lot.

May I ask in if the Volume is setup as a RAID zero or JBOD then adding 1 or 2 drive to an existing volume that has 4 drives shouldn't be a problem. Since there is no redundancy. Am I correct?

 

[david kennedy]

If i understand this you are stating you have two drives spanned and want to know if you can add more to this?

I dont see why not, but i must warn you that in a "span" or raid-zero config if you lose a single disk you lose all the data, not just what was on the failed disk. I obviously don't understand your needs so this could be acceptable, but feel i should at least mention this risk.

 

[RDCLAN]

Thank you very for your prompt reply. You are correct about the the spanned volume. I appreciate your feedback and have a wonderful day.