When replacing a failed hard drive in an MSA2212fc the system will not start rebuilding the drive until you assign it as a spare. This is somewhat different as most storage units will automatically add the replacement drive into the array.
For the MSA2212 after the disk is replaced go to Manage -> VDisk Configuration -> Add VDisk Spares. You will see the drive that you replaced with an available check box. If you scroll your mouse over the drive the information will show the drive as “available”. Place a check in the drive and click “add VDisk spares” under the enclosure view. The system will start rebuilding and will take quite some time.