ubuntu@ubuntu:~$ sudo dmraid -r
/dev/sda: "sil" and "nvidia" formats discovered (using nvidia)!
/dev/sdb: "sil" and "nvidia" formats discovered (using nvidia)!
/dev/sda: nvidia, "nvidia_egbeaddb", stripe, ok, 156301486 sectors, data@ 0
/dev/sdb: nvidia, "nvidia_egbeaddb", stripe, ok, 156301486 sectors, data@ 0
ubuntu@ubuntu:~$ sudo fdisk /dev/mapper/nvidia_egbeaddb

Unable to open /dev/mapper/nvidia_egbeaddb