Details of Modification
When the unit status of a network device is "unknown", it will not be released from maintenance mode.
For V3.1.1/V3.1.1A
When release from maintenance mode is performed for a network device with the unit status "unknown", the device will be released from maintenance mode.
For this version
When release from maintenance mode is performed for a network device with the unit status "unknown", the device will not be released from maintenance mode.
Corrective Action
When the unit status of the network device is "unknown", release it from maintenance mode after taking corrective action to make the unit status "normal".
