gmirror on root filesystem

[Josh Paetzel]

I'm trying to use gmirror on my root filesystem.  I've set sysctl 
kern.geom.debugflags to 16 and yet can't label the root partition.

# gmirror label -v root /dev/ad4s1a
Can't store metadata on /dev/ad4s1a: Operation not permitted.

I was able to do this for /var and /usr while they were mounted.  
Unless someone has any ideas the only solution I see is to put this 
disk in a different box to create the mirror.

-- 
Thanks,

Josh Paetzel