Command Reference Guide

N8406-022A 1Gb Intelligent L2 Switch Command Reference Guide (AOS) 92
Table 91 Bridge Spanning Tree Configuration Menu options
Command
Description
fwd <4-30>
Configures the bridge forward delay parameter. The forward delay parameter specifies the
amount of time that a bridge port has to wait before it changes from the listening state to the
learning state and from the learning state to the forwarding state. The range is 4 to 30
seconds, and the default is 15 seconds.
This command does not apply to MSTP. See the ―Common Internal Spanning Tree
configuration‖ section for more information.
cur
Displays the current bridge STP parameters.
When configuring STP bridge parameters, the following formulas must be used:
2*(fwd-1) > mxage
2*(hello+1) < mxage
Spanning Tree port configuration
Command: /cfg/l2/stp <STG number>/port <port number>
[Spanning Tree Port 1 Menu]
prior - Set port Priority (0-255)
cost - Set port Path Cost (1-65535 (802.1d) /
1-200000000 (MSTP/RSTP)/0 for auto)
link - Set port link type (auto, p2p, or shared; default: auto)
edge - Enables or disables this port as an edge port
fastfwd - Enable/disable Port Fast Forwarding mode
on - Turn port's Spanning Tree ON
off - Turn port's Spanning Tree OFF
cur - Display current port Spanning Tree parameters
By default for STP/PVST+, Spanning tree is turned Off for downlink ports (1-16), and turned On for cross-connect
ports (17-18), and uplink ports (20-24). By default for RSTP/MSTP, Spanning tree is turned Off for all downlink
ports (1-16) configured as Edge ports, and turned On for cross-connect ports (17-18), and all uplink ports (20-24).
Spanning tree port parameters are used to modify STP operation on an individual port basis. STP port parameters
include:
Port priority
Port path cost
The following table describes the Spanning Tree Port Configuration Menu options.
Table 92 Spanning Tree Port Configuration Menu options
Command
Description
prior <0-255>
Configures the port priority. The port priority helps determine which bridge port
becomes the designated port.
In a network topology that has multiple bridge ports connected to a single
segment, the port with the lowest port priority becomes the designated port for the
segment.
The range is 0 to 255, and the default is 128.
RSTP/MSTP: The range is 0 to 240, in steps of 16 (0, 16, 32...) and the default is
128.
cost <0-200000000>
Configures the port path cost. The port path cost is used to help determine the
designated port for a segment. Generally speaking, the faster the port, the lower
the path cost.
The range is 0 to 65535. The default is 4 for Gigabit ports except Port 19. A value
of 0 indicates that the default cost will be computed for an auto-negotiated link
speed. The default cost is 19 for 100Mb/s ports and 4 for Gigabit ports.
RSTP/MSTP: The range is 0 – 200000000, and the default is 20000 for Gigabit
ports except Port 19.
link auto|p2p|shared
Defines the type of link connected to the port, as follows:
auto: Configures the port to detect the link type, and automatically match its
settings.
p2p: Configures the port for Point-To-Point protocol.
shared: Configures the port to connect to a shared medium (usually a hub).
This command only applies when RSTP is turned on. See the ―Common Internal
Spanning Tree configuration‖ section for more information.