On a NETGEAR fully managed switch, Rapid Spanning Tree Protocol (RSTP, 802.1w) is globally enabled by default.
You can enable Multiple Spanning Tree Protocol (MSTP, 802.1s), which can support multiple spanning tree (MST) instances. Each MST instance consists of an ID, a priority value, and a VLAN ID. (We also refer to an MST instance as an MST ID.) You can assign one or more interfaces to an MST instance.
Note the following requirements for MST IDs:
- An MST ID must be in the range from 1 to 4094.
- The bridge priority value for an MST ID is a multiple of 4096. When switches or bridges are running STP, each is assigned a priority. After exchanging BPDUs, the switch with the lowest priority value becomes the root bridge. The bridge priority is a multiple of 4096. If you specify a priority that is not a multiple of 4096, the priority is automatically set to the next lowest priority that is a multiple of 4096. For example, if you set the priority to any value between 0 and 4095, the switch automatically sets the value to 0. The range is from 0 to 61440. The default is 32768.
- A VLAN that you add to an MST ID must already be defined. You can add more than one VLAN to an MST ID.
To use CLI commands to enable MSTP, configure MST instances 1 and 2, configure interface 1/0/3 as the MST port for MST instance 1, and configure interface 1/0/4 as the MST port for MST instance 2:
Enable MSTP:
(Netgear switch) (Config)# spanning-tree
(Netgear switch) (Config)# spanning-tree mode mst
Create MST instance 1 and associate VLAN 2 and VLAN 3 with MST instance 1:
(Netgear switch) (Config)# spanning-tree mst instance 1
(Netgear switch) (Config)# spanning-tree mst priority 1 4096
(Netgear switch) (Config)# spanning-tree mst vlan 1 2
(Netgear switch) (Config)# spanning-tree mst vlan 1 3
Create MST instance 2 and associate VLAN 12 and VLAN 13 with MST instance 2:
(Netgear switch) (Config)# spanning-tree mst instance 2
(Netgear switch) (Config)# spanning-tree mst priority 2 4096
(Netgear switch) (Config)# spanning-tree mst vlan 2 11
(Netgear switch) (Config)# spanning-tree mst vlan 2 12
Associate MST instance 1 with interface 1/0/3:
(Netgear switch) (Config)#interface 1/0/3
(Netgear switch) (Interface 1/0/3)# spanning-tree mst 1 port-priority 128
(Netgear switch) (Interface 1/0/3)# spanning-tree mst 1 cost 0
Associate MST instance 2 with interface 1/0/4:
(Netgear switch) (Config)#interface 1/0/4
(Netgear switch) (Interface 1/0/4)# spanning-tree mst 2 port-priority 128
(Netgear switch) (Interface 1/0/4)# spanning-tree mst 2 cost 0
For information about using the main user interface to configure MSTP, see How do I configure Multiple Spanning Tree Protocol (MSTP, 802.1s) using the main user interface on a fully managed switch?
To go to the STP landing page for fully managed switches, see What is SpanningTree Protocol (STP) and how does it work with a fully managed switch?