Problem using geom to mirror system

[Robert Fitzpatrick]

I am following the doc at http://people.freebsd.org/~rse/mirror/

While using Approach 2, the initial dump and reboot using the new gm0
mirror worked fine, but having a problem trying to add my da0 drive to
the mirror after the reboot. Can someone suggest what I've done wrong?

files# gmirror configure -a gm0s1
No such device: gm0s1.
files# df -h
Filesystem             Size    Used   Avail Capacity  Mounted on
/dev/mirror/gm0s1a     8.3G    1.2G    6.4G    16%    /
devfs                  1.0K    1.0K      0B   100%    /dev
/dev/mirror/datas1a     33G    4.0K     30G     0%    /data
files# ls -lah /dev/mirror/
total 1
dr-xr-xr-x  2 root  wheel          512 Dec 31  1969 .
dr-xr-xr-x  5 root  wheel          512 Dec 31  1969 ..
crw-r-----  1 root  operator    0, 116 May  4 23:43 data
crw-r-----  1 root  operator    0, 118 May  4 23:43 datas1
crw-r-----  1 root  operator    0, 121 May  4 19:43 datas1a
crw-r-----  1 root  operator    0, 122 May  4 23:43 datas1c
crw-r-----  1 root  operator    0, 109 May  4 23:43 gm0
crw-r-----  1 root  operator    0, 117 May  4 23:43 gm0s1
crw-r-----  1 root  operator    0, 119 May  4 19:43 gm0s1a
crw-r-----  1 root  operator    0, 120 May  4 23:43 gm0s1c
files# dmesg|grep gm0
GEOM_MIRROR: Device gm0 created (id=982386906).
GEOM_MIRROR: Device gm0: provider da1 detected.
GEOM_MIRROR: Device gm0: provider da1 activated.
GEOM_MIRROR: Device gm0: provider mirror/gm0 launched.
Trying to mount root from ufs:/dev/mirror/gm0s1a

-- 
Robert