ZFS on 4K drives - Expanding zpool and adding spares (gnop method)

Daniel Kalchev daniel at digsys.bg
Wed Jun 1 08:26:28 UTC 2011

On 01.06.11 11:19, Alexander Leidinger wrote:
> The 4k-sector part results in a pool specific config setting. I would 
> expect that if you add additional drives (no matter if 4k or not), 
> that the pool will continue to use 4k sectors. So I would expect that 
> you do not need gnop to expend an existing pool, but I have not 
> tested/verified this.
The ashift property is per-vdev, so you have to use gnop for each new 
vdev you add to the zpool. You also do not need to create gnop devices 
for all new drives -- the vdev will use the largest sector size of any 
member to calculate it's ashift value.

For example, creating the pool

gnop create -S 4096 disk0
zpool create test mirror disk0.nop disk1
zpool export test
gnop destroy disk0.nop
zpool import test

adding another vdev

gnop create -S 4096 disk2
zpool add test mirror disk2.nop disk3
zpool export test
gnop destroy disk2.nop
zpool import test


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