Abstract: A disaggregated network element of an optical transport network, addressable at a single IP address, includes an active management and control unit (MCU) communicatively coupled to a standby MCU by physical cables and multiple tributary units, each of which performs a function in a data plane that carries user traffic and is communicatively coupled to both MCUs by respective physical cables. The MCUs host respective copies of configuration information for the network element and synchronize the information between them. In response to a loss of communication between the MCUs, a tributary unit designated as a witness tributary unit is consulted to determine the status of the MCUs, after which actions are taken to provide control plane redundancy. In response to a failure of an MCU, a backup copy of the configuration information is stored on the witness tributary unit and subsequently synchronized with a copy stored on the remaining MCU.