Hi,

On Fri, Oct 7, 2011 at 2:13 PM, Warren Block <wbl...@wonkity.com> wrote:

I'd guess the procedure involves shooting your feet:

from `sys/geom/geom_subr.c':

/* If foot-shooting is enabled, any open on rank#1 is OK */ if ((g_debugflags & 16) && pp->geom->rank == 1) ;

this was introduced by phk@ himself in:

commit 641a10a0cb4ca86785ef13fce9343bc34c30f326 Author: phk <ph...@FreeBSD.org> Date: Wed Feb 12 09:48:27 2003 +0000

Implement a handle for efficient implementation of perforations in lower extremities.

Setting bit 4 in debugflags (sysctl kern.geom.debugflags=16) will allow any open to succeed on rank#1 providers. This will generally correspond to the physical disk devices: ad0, da0, md0 etc.

This fundamentally violates the mechanics of GEOMs autoconfiguration, and is only provided as a debugging facility, so obviously error reports on GEOM where this bit is or has been set will not be accepted.

- Arnaud