Looking at the Status Information on the MSTP network object under the BACnet Interface of the Automation Server, the status read online FALSE
Automation Server - AS
The AS is not being passed the network token.
If the Automation Server sees the token being passed on the bus but it never receives the token the AS will tag the MSTP network status as OFFLINE..
CAUSE: Baud rate mismatch with third party devices.
SOLUTION: If device does not support auto-baud change the speed of the MSTP to that of the device.
CAUSE: A device on the MSTP is using the same mac id as the MSTP port.
SOLUTION: Resolve the duplicate id issue.
CAUSE: A defective device on the MSTP
SOLUTION: Identify the defective device and replace it.