Trying to clone a ZFS drive, can't get ashift=12

Dimitry Andric dim at
Wed Apr 1 05:54:34 UTC 2015

On 01 Apr 2015, at 06:30, Daniel Eischen <deischen at> wrote:
> I have an Oracle (nee Sun) X4-2 server with identical 300GB SAS
> drives.  I did an MBR ZFS install from FreeBSD 10.1-RELEASE CD
> and have it updated to p6:
>  # zpool create -o cachefile=/tmp/newpool.cache bootpoolNew label/boot0
>  # zdb -U /tmp/newpool.cache | grep ashift
>              ashift: 9
> What gives?  How do I get it to use 4k?

sysctl vfs.zfs.min_auto_ashift=12

And also put that in your /etc/sysctl.conf.  I don't know why it isn't
the default yet... :)


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