Solved. Re: Dualboot and ZFS

Victor Sudakov vas at
Fri Mar 23 02:32:12 UTC 2018

Warren Block wrote:
> >> On Mon, 19 Mar 2018, Victor Sudakov wrote:
> >>>
> >>> sysctl kern.geom.debugflags=0x10
> >>
> >> Please reconsider doing this without it being required.  It means "allow
> >> destroying mounted partitions" and is usually not necessary.
> >
> > It is recommended, or even required ("must") by the zfsboot(8) man page:
> The vagueness here is from the "If the drive is currently in use".  It 
> could easily be replaced with "If the user wants to destroy data from a 
> drive that is currently being used".  

In my script, the ${DISK} is supposed to be a new disk onto which a
system is installed (cloned actually), so any data thereon would be
destroyed anyway.

> I would argue that we should 
> remove or rewrite that, as it is misleading.  Overwriting a drive that 
> is "in use" is generally exactly the opposite of what people want.

I'm afraid your concern is a bit misdirected. If you can suggest a way
to install zfsboot without dd, and document it in zfsboot(8) then of course
kern.geom.debugflags=0x10 is better avoided.

Victor Sudakov,  VAS4-RIPE, VAS47-RIPN

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