In storage area networking, Fabric OS (FOS) is the firmware for Brocade Communications Systems's Fibre Channel switches and Fibre Channel directors.

First generation

The first generation of Fabric OS was developed on top of a VxWorks kernel and was mainly used in the Brocade Silkworm 2000 and first 3000 series on Intel i960.

Second generation

The second generation of Fabric OS (4.0) was developed on a PowerPC platform, and uses MontaVista Linux, a Linux derivative with real-time performance enhancements. With the advent of MontaVista, switches and directors have the ability of hot firmware activation (without downtime for Fibre Channel fabric), and many useful diagnostic commands. According to free software licenses terms, Brocade provides access to sources of distributed free software, on which Fabric OS and other Brocade's software products are based.

Additional licensed products

Additional products for Fabric OS are offered by Brocade for one-time fee. They are licensed for use in a single specific switch (license key is coupled with device's serial number). Those include:

Versions