adding a RAID component

["Steven M. Bellovin" <smb%cs.columbia.edu@localhost>]

Short form: I'm trying to add a second drive for RAID mirroring -- how
do I do it?

Full story: I built a 5.0 system (per the instructions on the Wiki)
using just one drive of a RAID1 set.  I'd have added both components at
that time, but the machine I was working on didn't have a spare SATA
connector...

Anyway -- both disks are now in the proper machine.  I'm running from
raid0 on wd0e.  How do I persuade it to start using wd1 as the mirror
drive?

I have good console access but hitting the reset or power buttons are
difficult, so solutions that require nothing more than a 'shutdown -r'
are *strongly* preferred.

Here is the output of 'raidctl -s' and 'raidctl -G':


EMU# raidctl -s raid0
Components:
           /dev/wd0e: optimal
          component1: failed
No spares.
Component label for /dev/wd0e:
   Row: 0, Column: 0, Num Rows: 1, Num Columns: 2
   Version: 2, Serial Number: 2009080901, Mod Counter: 201
   Clean: No, Status: 0
   sectPerSU: 128, SUsPerPU: 1, SUsPerRU: 1
   Queue size: 100, blocksize: 512, numBlocks: 1953524992
   RAID Level: 1
   Autoconfig: Yes
   Root partition: Yes
   Last configured as: raid0
component1 status is: failed.  Skipping label.
Parity status: DIRTY
Reconstruction is 100% complete.
Parity Re-write is 100% complete.
Copyback is 100% complete.
EMU# raidctl -G raid0
# raidctl config file for /dev/rraid0d

START array
# numRow numCol numSpare
1 2 0

START disks
/dev/wd0e
component1

START layout
# sectPerSU SUsPerParityUnit SUsPerReconUnit RAID_level_1
128 1 1 1

START queue
fifo 100


                --Steve Bellovin, http://www.cs.columbia.edu/~smb