"Handbook / Chapter 19 GEOM" question

[Pavel Sukhoy]

Hello all,

Could you tell me some clarifications about section "19.4.1 Mirroring Primary Disks"?

In this section I see sample command: 

# sysctl kern.geom.debugflags=17

but I can't understand why this kernel tunable should be 17? 

If I will look through the /usr/src/sys/geom/geom_kern.c

I will see this:
"...
TUNABLE_INT("kern.geom.debugflags", &g_debugflags);
..."

and in /usr/src/sys/geom/geom_subr.c

I will see this:
"...
       /* If foot-shooting is enabled, any open on rank#1 is OK */
        if ((g_debugflags & 16) && pp->geom->rank == 1);
..."

So I think that it should be 16 or I looked for it in inappropriate files.

Thank you beforehand.
-- 
With best regards,
Pavel Sukhoy