GEOM's RAID level support

[Adrian Wontroba]

On Sat, Oct 08, 2005 at 08:57:51AM +0200, Pawel Jakub Dawidek wrote:
> On Sat, Oct 08, 2005 at 02:35:21AM +0100, Adrian Wontroba wrote:
> +> mirror/gm0  COMPLETE  ad4a
> +>                       ad6a
> +>                       ad8a
> +>                       ad10a
> 
> Isn't that waste of space?

Yes, but it isn't a lot of space (1 GB on each of four 150 GB disks),
and it gives me the comfort blanket of being able to boot from any disk.

> +> At work, I've developed a makefile based version of RSE's "single disk
> +> to two disk" approach.  If there is any interest, I'll ask my boss if I
> +> can release it.
 
> Nice idea, but I think at this point it is too much specific for you
> configuration. It'd be much useful when it will be more general somehow.

The makefile I produced at work is much more general. Provided the first
disk is no larger than the second, and contains a single *s1 slice, it
will build an two disk system equivalent to the first, with the same
partition sizes. It also has a fall back for the "almost the same size
but different geometry" gotcha. I hate this ancient CHS cruft.

It is being used soon after sysinstall by UNIX novices.  Of course, it
will probably be totally redundant once Craig makes sysinstall GEOM
aware.

-- 
Adrian Wontroba