"Handbook / Chapter 19 GEOM" question

Pavel Sukhoy sukhoy at nic.ru
Thu Feb 24 13:07:17 UTC 2011


On Thursday 24 of February 2011 15:47:15 Sergey Kandaurov wrote:
> 2011/2/24 Pavel Sukhoy <sukhoy at nic.ru>:
> > 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.
> >
> 
> 17 additionally enables the first bit to trace G_T_TOPOLOGY events.
> There is a full list in geom/geom_int.h:
> /*
>  * 1    G_T_TOPOLOGY
>  * 2    G_T_BIO
>  * 4    G_T_ACCESS
>  * 8    (unused)
>  * 16   Allow footshooting on rank#1 providers
>  * 32   G_T_DETAILS
>  */
> 
> 

Thanks a lot.

-- 
With best regards,
Pavel Sukhoy      



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