NETGEAR S3300 - MST Port Configuration

Configuring Switching
166
S3300 Smart Managed Pro Switch
MST Port Configuration
Use the MST Port Configuration screen to configure and display Multiple Spanning Tree
(MST) settings on a specific port on the switch.
A port can become Diagnostically Disabled (D-Disable) when DOT1S experiences a severe
error condition. The most common cause is when the DOT1S software experiences BPDU
flooding. The flooding criteria is such that DOT1S receives more than 15 BPDUs in a
3-second interval. The other causes for DOT1S D-Disable are extremely rare.
 To configure MST port settings:
1. Select Switching > STP > Advanced > MST Port Configuration.
Note: If no MST instances have been configured on the switch, the screen
displays a “No MSTs Available” message.
2. Select the ports or LAGs to configure.
For information about how to select and configure one or more ports or LAGs, see
Configuring Interface Settings on page 32.
3. Configure the MST values for the selected port(s) or LAG(s):
• Port Priority. The priority for a particular port within the selected MST instance. The
port priority is set in multiples of 16. If you specify a value that is not a multiple of 16,
the priority is set to the priority is automatically set to the next lowest priority that is a
multiple of 16. For example, if you set a value between 0 and 15, the priority is set to
0. If you specify a number between 16 and 31, the priority is set to 16. It takes a value
in the range of 0–240.
• Port Path Cost. Set the Path Cost to a new value for the specified port in the selected
MST instance. It takes a value in the range of 0–200000000.
4. Click the Apply button.
The following table describes the read-only MST port configuration information displayed on
the Spanning Tree CST Configuration screen
Table 56. MST port status information
Field Description
Auto-calculated Port Path
Cost
Displays whether the path cost is automatically calculated (Enabled) or not
(Disabled). Path cost is calculated based on the link speed of the port if the
configured value for Port Path Cost is zero.
Port ID The port identifier for the specified port within the selected MST instance. It is
made up from the port priority and the interface number of the port.
Port Up Time Since Counters
Last Cleared
Time since the counters were last cleared, displayed in Days, Hours, Minutes,
and Seconds.