Changing the Network Operating System

ExtremeSwitching Universal Hardware switches can run two different operating systems: Switch Engine (formerly EXOS) (default) or Fabric Engine (formerly VOSS).

Making Your Initial Network Operating System Selection

You can make your initial selection of the operating system using:
  • ExtremeCloud™ IQ (see ExtremeCloud IQ Agent Support)—You can select your network operating system when purchasing your switch, which associates the switch serial number with your desired network operating system, which then causes the desired network operating system to be loaded during ExtremeCloud onboarding. For more information about using ExtremeCloud IQ, go to
  • Extreme Management Center— see Extreme Management Center User Guide
  • Manually during boot-up:
    • Bootloader—When the message Starting Default Bootloader ...Press and hold the <spacebar> to enter the bootrom appears, press and hold the space bar until the boot menu appears (you have 30 seconds):
      *** 5320-48T-8XE Boot Menu ( ) ***
           EXOS: Default
           EXOS: Primary 31.6..
           EXOS: Secondary 31.6..
           EXOS: Primary 31.6.. with default configuration
           EXOS: Secondary 31.6.. with default configuration
           EXOS: Rescue
           Change the switch OS to VOSS
           Run Manufacturing Diagnostics
           Update bootloader
           Reboot system

      Use the up and down arrow keys to select Change the switch OS to VOSS, and then press Enter.

    • Safe defaults mode start-up menu—When the question Would you like to change the switch OS to VOSS? [y/N/q] appears:
      • For Switch Engine, type N.
      • For Fabric Engine, type y.

    Continue to log onto the switch. For more information about logging onto the switch, see the ExtremeXOS 31.7 User Guide .

Changing Your Network Operating System

You can change your network operating system selection at any time.


Changing your network operating systems deletes all configuration files, debug information, logs, events, and statistics information of the previous network operating system.


If you anticipate ever changing the operating system to Fabric Engine, and you want to statically assign IP addresses on the DHCP server, then it is recommended to assign them based on the DHCP client ID. For more information about this issue, see the Using a BOOTP or DHCP Server topic in the ExtremeXOS 31.7 User Guide .