NX-OS is a network operating system for the Nexus-series Ethernet switches and MDS-series Fibre Channel storage area network switches made by Cisco Systems.
[1] It evolved from the Cisco operating system SAN-OS, originally developed for its MDS switches.
Cisco is responsible for its development and maintenance.
[1] The command-line interface of NX-OS is similar to that of Cisco IOS.
Cisco is responsible for development and maintenance of NX-OS.