Configuring RAID1 after install

[John Lyon]

Maybe I'm extra dense this morning, but I'd like to configure RAID1 on a box
that's already installed.

Judging by what Webmin is telling me, I can't create a raid device using my
boot drive, without destroying the boot drive to create the raid array.
(Except - I want my current boot drive mirrored, in case of drive
failure...)

Am I right, or am I missing something?

-- 
John Lyon
Austin TX