Promise RAID / ata problem

[Derek Holden]

Greetings,

I have a Promise Fasttrak TX4200 running a single mirrored array under 5.5.
Everything's been great for nearly a year until a recent reboot.  It appears
that the two disk mirrored array is coming up as two arrays with a single
disk attached:

Before:

kernel: acd0: CDRW <SONY CD-RW CRX140E/1.0n> at ata1-slave UDMA33
kernel: ad6: 305245MB <Seagate ST3320620AS 3.AAC> at ata3-master SATA150
kernel: ad10: 305245MB <Seagate ST3320620AS 3.AAC> at ata5-master SATA150
kernel: ar0: 305175MB <Promise Fasttrak RAID1> status: READY
kernel: ar0: disk0 READY (master) using ad10 at ata5-master
kernel: ar0: disk1 READY (mirror) using ad6 at ata3-master

After:

kernel: acd0: CDRW <SONY CD-RW CRX140E/1.0n> at ata1-slave UDMA33
kernel: ad6: 305245MB <Seagate ST3320620AS 3.AAC> at ata3-master SATA150
kernel: ad10: 305245MB <Seagate ST3320620AS 3.AAC> at ata5-master SATA150
kernel: ar0: disk0 DOWN no device found for this subdisk
kernel: ar0: disk1 READY (mirror) using ad6 at ata3-master
kernel: ar1: 305175MB <Promise Fasttrak RAID1> status: DEGRADED
kernel: ar1: disk0 READY (master) using ad10 at ata5-master
kernel: ar1: disk1 DOWN no device found for this subdisk

# atacontrol status ar0
ar0: ATA RAID1 subdisks: DOWN ad6 status: DEGRADED

# atacontrol status ar1
ar1: ATA RAID1 subdisks: ad10 DOWN status: DEGRADED

Nothing's was changed on the machine.  I'm looking for any ideas on the best
way to re-establish the single mirrored array.  Thanks a lot,