If you wish to modify a MST Instance, you must first delete the instance and then redefine it. Refer to “Create VLAN Mapping to MST Instance” on page 135 for more information.
Delete MST Instance
1. In the Action column of the table, click on Delete for the MST Instance that want to delete.
The instance is deleted along with the mapped associations to the VLANs that are listed.
2. From the main menu on the left side of the page, select Save Configuration to Flash to permanently save your changes.
Port Configuration
To configure the MSTP parameters for each of the ports, perform the following procedure:
1. From the main menu on the left side of the page, select Bridge.
The Bridge folder expands.
2. From the Bridge folder, select the Spanning Tree folder.
The Spanning Tree folder expands.
3. From the Spanning Tree folder, select the MSTP folder.
The MSTP folder expands.
4. From the MSTP folder, select MSTP Port Configuration.
The AT-GS950/8 MSTP Port Configuration Page is displayed. See Figure 46.
Figure 46. AT-GS950/8 MSTP Port Configuration Page You may choose a port and configure its MSTP parameters on this page. The following information is displayed:
Port - Indicates ports 1 through 8on the AT-GS950/8 switch. Use the All row to apply the same settings for the Point-to-Point Status, Edge Port, MSTP Status, Protocol Migration, AutoEdge Status, Restricted Role, Restricted TCN fields to all the ports on your switch.
Path Cost - Specifies the cost of a port to the root.
Priority - Specifies the spanning tree port priority.
PointToPoint Status - Indicates if the port is connected to another network device (point-to-point) in the network topology. See “Point-to-Point and Edge Ports” on page 116 for more information.
network topology.
ForcedFalse - The port is not connected to a network device in the network topology.
Auto - The switch will automatically determine the port type.
Edge Port - Indicates if a port is connected to an edge device in the network topology or not. See “Point-to-Point and Edge Ports”
on page 116 for more information.
True - The port is connected to an edge device and the port will always be in a forwarding state.
False - The port is not connected to an edge device.
MSTP Status - Indicates if MSTP is Enabled or Disabled.
Enabled - MSTP is active on the port.
Disabled - MSTP is inactive on the port.
Protocol Migration - A switch running MSTP supports a built-in protocol migration mechanism that enables it to inter-operate with legacy 802.1D switches.
True - The switch is able to inter-operate with 802.1D BPDU packets.
False - This switch can only operate with RSTP and MSTP packets.
Hello Time - The Hello Time is frequency with which the root bridge sends out a BPDU. See “Hello Time and Bridge Protocol Data Units (BPDU)” on page 116 for more information.
AutoEdge Status - This parameter allows the switch to detect if the port functioning as an edge port.
Restricted Role - This parameter prevents the port from becoming a root port.
True - The port is prevented from being a root port or a port that is used to communicate with the root bridge.
False - This switch can only operate with RSTP and MSTP packets.
The net effect of setting all ports on the switch to True is that it forces the switch into the role of the root bridge regardless of other path costs in the network.
Restricted TCN - The Restricted TCN parameter does not allow Topology Change Notification (TCN) BPDUs to be processed on the port.
True - The port cannot process receive/transmit TCN BPDUs.
False - The port can process receive/transmit TCN BPDU packets.
5. Once you have configured the parameters, click Apply in the Action column.
6. If you choose to change the MSTP port configuration for other ports, repeat steps 4 and 5.
7. From the main menu on the left side of the page, select Save Configuration to Flash to permanently save your changes.
Port Settings
To configure the MSTP port settings, perform the following procedure:
1. From the main menu on the left side of the page, select Bridge.
The Bridge folder expands.
2. From the Bridge folder, select the Spanning Tree folder.
The Spanning Tree folder expands.
3. From the Spanning Tree folder, select the MSTP folder.
The MSTP folder expands.
4. From the MSTP folder, select MSTP Port Settings.
The MSTP Port Settings Page is displayed. See Figure 47.
Figure 47. MSTP Port Settings Page
You may choose a port and configure its MSTP parameters on this page. The following information is displayed:
Port - Indicates ports 1 through 8 on the AT-GS950/8 switch. Use the All row to apply the same settings for the Port State field to all the ports on your switch.
MSTP Instance ID - Indicates the MSTP Instance that associated with this port.
Port State - This parameter activates or deactivates the port.
Select one of the following choices from the pull-down menu:
Enable - Allows the port to forward packets.
Disable - Does not allows the port to forward packets.
Priority - This is the port priority used by MSTP in calculating path costs when two ports on the switch have the same port cost.
Cost - This is the port cost used by MSTP when calculating path cost to the root bridge.
5. Once you have configured the parameters, click Apply in the Action column.
6. If you choose to change the MSTP port settings for other ports, repeat steps 4 and 5.
7. From the main menu on the left side of the page, select Save Configuration to Flash to permanently save your changes.