Q: I have a degraded RAID with multiple failed drives. I have replaced all of the drives, but when I try to rebuild on all of these drives the operation fails. Why is this happening?
A: MegaRAID controllers can only rebuild one drive at a time. You will need to start a rebuild on a single drive, and then wait for each rebuild to finish before starting the next one.
You can check the status of a rebuild with the following commands:
# MegaCli64 -PDRbld -ShowProg -aALL
# storcli64 /cx/ex/sx show rebuild