Comment 32 for bug 112402

Portending, the installer will always see the two physical disks... the question is, does it also see the /dev/mapper/xxxx virtual raid disk? If not, and you want to see if you can find the metadata on the disk, then do this:

To start, you may as well blow away any partitions on the disk. Then we want to zero out the last 2 MB of the disk so you can be sure that anything written there is going to have to do with the raid metadata. Do sudo dd if=/dev/zero of=/dev/sda seek=156299488. Repeat for each disk in the array. Then reboot and go into the bios and make sure that you have the raid functions enabled, but when you go into the raid set configuration screen, it should not recognize any raid sets. Then create one. Finally, look at the data on the last 2 MB again.