ROM Monitor (ROMMON)

ROMMON, also known as the boot loader, is firmware that runs when the device is powered up or reset. It initializes the processor hardware and boots the operating system software (Cisco IOS XE software image). The ROMMON is stored on the following Serial Peripheral Interface (SPI) flash devices on your switch:

• Primary: The ROMMON stored here is the one the system boots every time the device is powered-on or reset.

• Golden: The ROMMON stored here is a backup copy. If the one in the primary is corrupted, the system automatically boots the ROMMON in the golden SPI flash device.

ROMMON upgrades may be required to resolve firmware defects, or to support new features, but there may not be new versions with every release.

Complex Programmable Logic Device (CPLD)

CPLD refers to hardware-programmable firmware. CPLD upgrades are not mandatory but may be required to resolve firmware defects, or to support new features. The upgrade process can be completed after upgrading the software image. There may not be new CPLD versions with every release.

The following table provides ROMMON and CPLD version information for the Cisco Catalyst 9400 Series Supervisor Modules. For ROMMON and CPLD version information of Cisco IOS XE 16.x.x releases, refer to the corresponding Cisco IOS XE 16.x.x release notes of the respective platform.