A single disk failure is the most common failure affecting storage systems today. When a disk fails, that disk is removed and replaced. The replacement disk is then reconstructed. The disk rebuild operation did not affect the write rate, video quality, or result in dropped video.
The PowerScale cluster was protected using a +2 protection scheme that allows for two simultaneous disk failures. For the test, two disks are failed and then recovered. The SmartFail process started and the CPU utilization of the node increased with no observed effect to the write streams.
The PowerEdge servers were protected using RAID with hot spare disks. For the test, disk failure scenarios were induced and the data rebuild to the hot spare disks was observed with effect to write bandwidth.