ZFS How to set up ashift?

[Annalesa]

Can I set a 14 ashift on 4k disk?

 

[SirDice]

16K is a multiple of 4K, so it should be fine.

 

[mer]

sysctl -w vfs.zfs.min_auto_ashift=14
I believe you want to do that prior to creating any zpool

 

[SirDice]

sysctl -w vfs.zfs.min_auto_ashift=14

Old one, should still work though. New one is vfs.zfs.vdev.min_auto_ashift

 

[msplsh]

Would not mess with default ashift. ZFS will happily mix ashift disks in zvols with no notice and then refuse to let you drop them out when it's repair or emergency time. Learned this by experience.

 

[mer]

Would not mess with default ashift. ZFS will happily mix ashift disks in zvols with no notice and then refuse to let you drop them out when it's repair or emergency time. Learned this by experience.

I think there are valid reasons to muck with ashift. But I also think if you are mucking with ashift you should know the caveats and not mix them.