Filter
Top Products
Spanning Tree Algorithm Configuration
3-145
3
by auto-detection, as described for Admin Link Type in STA Port Configuration on
page 3-147.
• Oper Edge Port – This parameter is initialized to the setting for Admin Edge Port
in STA Port Configuration on page 3-147 (i.e., true or false), but will be set to false
if a BPDU is received, indicating that another bridge is attached to this port.
• Port Role – Roles are assigned according to whether the port is part of the active
topology connecting the bridge to the root bridge (i.e., root port), connecting a LAN
through the bridge to the root bridge (i.e., designated port), or is an alternate or
backup port that may provide connectivity if other bridges, bridge ports, or LANs
fail or are removed. The role is set to disabled (i.e., disabled port) if a port has no
role within the spanning tree.
• Trunk Member – Indicates if a port is a member of a trunk.
(STA Port Information only)
These additional parameters are only displayed for the CLI:
• Admin status – Shows if this interface is enabled.
• Path cost – This parameter is used by the STA to determine the best path
between devices. Therefore, lower values should be assigned to ports attached to
faster media, and higher values assigned to ports with slower media. (Path cost
takes precedence over port priority.)
• Priority – Defines the priority used for this port in the Spanning Tree Algorithm. If
the path cost for all ports on a switch is the same, the port with the highest priority
(i.e., lowest value) will be configured as an active link in the Spanning Tree. This
makes a port with higher priority less likely to be blocked if the Spanning Tree
Alternate port receives more
useful BPDUs from another
bridge and is therefore not
selected as the designated
port.
x
R: Root Port
A: Alternate Port
D: Designated Port
B: Backup Port
RR
ADB
Backup port receives more
useful BPDUs from the same
bridge and is therefore not
selected as the designated
port.
x
RR
ADB