Re: 8.0 booter: chain-boot sd0 if present?

[Mouse <mouse%Rodents-Montreal.ORG@localhost>]

>> It occurred to me that in principle it should be possible to work
>> around this in the booter, [...]

Incidentally, I've got this working, by creating an alternative MBR
bootblock, sibling to /usr/mdec/mbr, that boots disk 1 if present,
otherwise booting the active partition from disk 0.

> Alternatively, you can shift this check to userland.  In one of the
> rc files,

There are no rc files.  /sbin/init in the installed system is the
application, not a normal init.

Also,

> Maybe using the init.root sysctl node (see init(8)).

$ sysctl init.root
sysctl: second level name 'root' in 'init.root' is invalid
$ 

Curiously, on the same system as above, init(8) does say

          If value of the "init.root" sysctl node is not equal to / at this
          point, [...]

which makes me wonder what I'm missing.

This check could be done in the application, it's true, but (as you
point out) it imposes the installed kernel on the installation
operation, which I would rather avoid, and it involves writing a live
filesystem, which while perhaps tolerable is also something I would
rather avoid.

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