Gmirror on a partition of a slice

[David Cecil]

Hi,

I didn't think it was possible to mirror just a partition (as opposed to 
a slice).  As far as I know, you can mirror a whole disk or a slice, but 
not a BSD partition.  Has this changed?  Why don't you just mirror the 
slice?

Regards,
Dave

ext n j wrote:
> Hello,
>
> I've originally sent this mail to -questions, but -geom is probably
> the better place to ask for pointers to any help regarding installing
> gmirror on a partition of a slice. Here's the problem.
>
> Using http://www.onlamp.com/pub/a/bsd/2005/11/10/FreeBSD_Basics.html
> and http://people.freebsd.org/~rse/mirror/ as pointers, as well as
> handbook and man pages, I tried to set up gmirror on a partition of a
> slice the following way (using identical 1Gb disks da0 & da1):
>
> 1) install FreeBSD on 1st disk /dev/da0s1a
>
> 2) create slice on 2nd disk fdisk -BI /dev/da1
>
> 3) bsdlabel -w -B /dev/da1s1
>
> 4) edit BSD label to create a ~500 Mb partition for gmirror
> a:  1000000       16    4.2BSD       2048     16384    8
> c:  2097120        0    unused        0     0         # "raw" part
>
> 5) gmirror label -h -n -b round-robin gm0 /dev/da1s1a to create mirror
>
> 6) fdisk -BI /dev/mirror/gm0 to create a slice in gm0
>
> 7) bsdlabel -w -B /dev/mirror/gm0s1 to create root partition
> a:  995951   16     4.2BSD     2048 16384 8
> c:  995967    0       unused        0     0         # "raw" part
>
> 8) newfs, mount, dump/restore to /dev/mirror/gm0s1a, modify fstab,
> loader.conf, create boot.config to boot off mirror
>
> 9) reboot
>
> ... and at that point I get "Not ufs" and "No /boot/loader". Any kind
> of input, be it a link to some material on the web or a proper
> sequence of command is much appreciated. I've googled a lot and
> haven't found any examples/howtos/tutorials on how to set up what I'm
> trying to do.
>
> Thanks,
>