The Cisco Nexus 2000 Series design aligns with that of servers. It offers front-to-back cooling, compatible with data center hot-aisle and cold-aisle designs, all switch ports at the rear of the unit in close proximity to server ports, and all user-serviceable components accessible from the front panel. It also offers back-to-front cooling, with switch ports in front of the chassis, aligned with the cold aisle, for optimized cabling in network racks. The Cisco Nexus 2000 Series is built for nonstop operation, with redundant hot-swappable power supplies and a hot-swappable fan tray with redundant fans. Its compact 1-rack-unit (1RU) form factor takes up relatively little space, making it easy to incorporate into rack designs. The fabric extenders are available in several models to provide speed, connectivity, and port-density options.