A method in a network device in a network, the method comprising: initiating a software upgrade of a control plane of the network device, wherein port roles and states pertaining to a current spanning tree need to be re-computed; subsequent to initiating the software upgrade, starting a timer to mark a beginning of a quiescent period; instantiating a spanning tree protocol, STP, agent to perform: disabling transmission of bridge protocol data units, BPDUs, to other network devices in the network, wherein the network device does not transmit BPDUs to other network devices during the quiescent period; receiving first BPDUs from the other network devices during the quiescent period; and updating port information of ports (610a - 610p) of the network device based on the first BPDUs without transmitting any BPDUs to the other network devices during the quiescent period, wherein updating port information includes updating port role and/or port state information of the ports (610a - 610p) of the network device based on the received first BPDUs; and subsequent to expiration of the timer: enabling transmission of BPDUs to other network devices in the network; receiving second BPDUs from the other network devices; and updating port information of ports (610a - 610p) of the network device based on the second BPDUs, including transmitting BPDUs to the other network devices for at least some of the second BPDUs. initiating a software upgrade of a control plane of the network device, wherein port roles and states pertaining to a current spanning tree need to be re-computed; subsequent to initiating the software upgrade, starting a timer to mark a beginning of a quiescent period; instantiating a spanning tree protocol, STP, agent to perform: disabling transmission of bridge protocol data units, BPDUs, to other network devices in the network, wherein the network device does not transmit BPDUs to other network devices during the quiescent period; receiving first BPDUs from the other network devices during the quiescent period; and updating port information of ports (610a - 610p) of the network device based on the first BPDUs without transmitting any BPDUs to the other network devices during the quiescent period, wherein updating port information includes updating port role and/or port state information of the ports (610a - 610p) of the network device based on the received first BPDUs; and disabling transmission of bridge protocol data units, BPDUs, to other network devices in the network, wherein the network device does not transmit BPDUs to other network devices during the quiescent period; receiving first BPDUs from the other network devices during the quiescent period; and updating port information of ports (610a - 610p) of the network device based on the first BPDUs without transmitting any BPDUs to the other network devices during the quiescent period, wherein updating port information includes updating port role and/or port state information of the ports (610a - 610p) of the network device based on the received first BPDUs; and subsequent to expiration of the timer: enabling transmission of BPDUs to other network devices in the network; receiving second BPDUs from the other network devices; and updating port information of ports (610a - 610p) of the network device based on the second BPDUs, including transmitting BPDUs to the other network devices for at least some of the second BPDUs. enabling transmission of BPDUs to other network devices in the network; receiving second BPDUs from the other network devices; and updating port information of ports (610a - 610p) of the network device based on the second BPDUs, including transmitting BPDUs to the other network devices for at least some of the second BPDUs.