A 4U controller assembly with two HSV210-B controllers and two M5314C 3U dual-redundant FC Loop 14-bay disk enclosures. It can be Factory Configured with additional drive enclosures. For configurations with more than four Drive enclosures the FC loop switches must be included. It can also be field upgraded up to a 2C12D configuration with the addition of drive enclosures and FC loop switches. With the addition of another rack the EVA8100 can support up to 2C18D.