ZFS mounting order

[Shane Ambler]

On 21/05/2012 00:11, Chris Brennan (lists) wrote:
> Greetings!
>
> I have a FreeBSD 9 system with 3 different ZFS pools on it. I am
> booting from a ro CF Card w/o any major issues, the problem I am
> encountering is that zroot needs to be mounted at boot first, because
> it contains /usr, zhome and tank contain other various sub-partitions
> of /usr.
>
> Also, zroot causes me a lot of problems when I try to do "zpool
> import", when zpool gets to probing zroot, I get g_vfs errors printed
> to the console and the hacnine hangs till I reset it (which is
> obviously not acceptable behavior.) I was able to get around this when
> booting to my cf card by making / ro, which was my intention all along
> for that media.) I suspect this happens because there is a on that
> volume that is trying to replace something on / on either the USB boot
> img or on my CF card and this might be causing either to freak out.
>
> So I dunno what to do to get this working the way it should and some
> guidence would be greatly appreciated!
>

Sounds like something I came across and haven't gathered more details to 
submit a pr yet.

I think there is a problem when two zpools have the same mountpoint - 
either / or legacy or one of each that prevents startup. Also zfs 
filesystems with matching mountpoints appear to mount together and cause 
issues, not sure if this extends to existing ufs mount points.

Check the mountpoint settings on each filesystem 'zfs get mountpoint' 
will list them all.