software raid questions

[Jeffrey Ross]

Can I take a running raid 1 (Mirror) logically fail a drive and remove it
from the array and then reload the system using only the drive that was
logically failed from the system?

Basically the goal is to be able to apply patches/changes etc and be able
to test them and still have an easy way to roll back to the previous
system state, and then rebuild the array of which ever drive I consider to
be stable.

TIA, Jeff