Traditionally, booting an Ubuntu installation with the root filesystem on a degraded RAID drops the system into a busybox prompt in the initramfs.
This is a very conservative approach, allowing the system administrator to consciously recognize that the system has lost a RAID disk, and preventing the system from booting into an unprotected situation.
Nachdem Google nun an viele Nexus S-Geräte Android 4.0.3 via OTA-Update verteilt hat, verlieren Viele leider ihre Root-Rechte am Gerät. Mit dieser Anleitung