The disk shred operation destroys the label for the disk and recreates the label. If the shred operation aborts in the middle or the system crashes, the disk might go in an error state with no label.
To correct the error state of the disk
# /etc/vx/bin/vxdisksetup -i disk
# /etc/vx/bin/vxdiskunsetup [-Cf] -o shred[=1|3|7] disk...