Hardware and RAID configuration
This was an Iomega StorCenter ix4-200d NAS with 4x2TB drives.
According to the customer, the NAS contained a Linux-based 4-drive RAID 5 volume.
There were two main partitions: one to store a shared folder and the other to use as iSCSI storage
for a Citrix XenServer.
The continuous reboots made the NAS inaccessible. All four drives seemed healthy. Upon reboot the NAS displayed the error message "insufficient disks for RAID5".
- Each hard drive was divided into two partitions. The first and small partition formed a mirrored volume
holding the NAS operating system. The second and much larger partition formed a RAID 5 holding an XFS volume.
- We performed a RAID analysis to compute the RAID 5 settings (block-size, disk order, parity rotation and starting sector).
- The root folder of the XFS volume was intact.
- File Scavenger® was used to reconstruct the RAID 5. The XFS volume was automatically detected by the quick scan and all data was displayed.
- The iSCSI storage was actually a huge 1.95 TB file under the folder \iSCSI.
This was a complete recovery.