On boot I am getting:
WARNING: md: failed to open. open error on /dev/dsk/c5t2d0s0

#metastat is reporting "State: unavailable". And doing "metastat -i" as it suggests doesn't change anything
 
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d1002: Soft Partition
    Device: d100
    State: Okay
    Size: 578813952 blocks (276 GB)
        Extent              Start Block              Block count
             0                201326688                578813952

d100: RAID
    State: Unavailable
    Invoke: metastat -i
    Interlace: 32 blocks
    Size: 782219520 blocks (372 GB)
Original device:
    Size: 782220032 blocks (372 GB)
        Device     Start Block  Dbase        State Reloc  Hot Spare
        c0t1d0s0        330        No            -   Yes
        c2t1d0s0        330        No            -   Yes
        c3t1d0s0        330        No            -   Yes
        c4t1d0s0        330        No            -   Yes
        c5t1d0s0        330        No            -   Yes
        c0t3d0s0        330        No            -   Yes
        c4t3d0s0        330        No            -   Yes
        c3t3d0s0        330        No            -   Yes
        c5t3d0s0        330        No            -   Yes
        c2t3d0s0        330        No            -   Yes
        c2t2d0s0        330        No            -   Yes
        c5t2d0s0        330        No            -   Yes

d1001: Soft Partition
    Device: d100
    State: Okay
    Size: 67108864 blocks (32 GB)
        Extent              Start Block              Block count
             0                134217792                 67108864
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