Description of problem:
it would be nice to be able to install in degraded raid1 mode.

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
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Actual results:


Expected results:


Additional info:
scenario:
o) 2 brand new shiny very expensive SATA seagate drives.
o) install FC4 in raid1 mode.
o) one of the drives is kaput, _completely_ dead. need to RMA. curses. foiled again.
o) machine needs to be installed and running asap, one way or another.
o) machine cannot be easily taken offline after the fact to reinstall as raid1.

an option to install in raid1 degraded mode (eg missing disk, will be installed
and synced later) would be ideal for this situation. eg we can install raid1
with a missing disk, add it later and resync it up later when the drive is
returned from RMA. in the meantime the machine is up and running.

anaconda will not currently let us do this. it insists on having all drives
present and operational at install time.