For an XtremIO X2 two X-Brick system installation, only two IP addresses are required because the entire system is managed through the first X-Brick. This is in line with the design of the XtremIO X2 architecture, which allows for a single management point for multiple X-Bricks. The XMS (XtremIO Management Server) manages multiple XtremIO arrays and requires an IP address for each X-Brick in the cluster1. In a two X-Brick system, the first X-Brick acts as the primary management point, and the second X-Brick is managed through it, thus only necessitating two IP addresses for management purposes2.