All ProLiant servers have a system ROM.
A system reboot is required for a ROM upgrade to take effect. For disaster recovery or ROM downgrade purposes, backups of the most current ROM image are available in either redundant ROM or a ROM backup.
ProLiant servers support either the redundant ROM feature or the Disaster Recovery feature. Both assist with the management of system ROM revisions and ensure the proper operation of the platform if a failure occurs during the firmware upgrade process.