Edge-Core ECS4310-26T Management Manual page 77

Discarding — Port receives STP configuration messages, but does
■
not forward packets.
Learning — Port has transmitted configuration messages for an
■
interval set by the Forward Delay parameter without receiving
contradictory information. Port address table is cleared, and the
port begins learning addresses.
Forwarding — Port forwards packets, and continues learning
■
addresses.
The rules defining port status are:
A port on a network segment with no other STP compliant bridging
■
device is always forwarding.
If two ports of a switch are connected to the same segment and
■
there is no other STP device attached to this segment, the port with
the smaller ID forwards packets and the other is discarding.
All ports are discarding when the switch is booted, then some of
■
them change state to learning, and then to forwarding.
◆ Role — Roles are assigned according to whether the port is part of the
active topology connecting the bridge to the root bridge (that is, root
port), connecting a LAN through the bridge to the root bridge (that is,
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 (that is, disabled port) if a port has no role
within the spanning tree.
◆ Path Cost — The path cost setting for the port:
Config — The administrator configured path cost setting.
■
Actual — The contribution of this port to the path cost of paths
■
towards the spanning tree root which include this port.
Priority — Defines the priority used for this port in the Spanning Tree.
◆
If the path cost for all ports on a switch is the same, the port with the
highest priority (that is, 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 Protocol is detecting network
loops. Where more than one port is assigned the highest priority, the
port with the lowest numeric identifier will be enabled.
P2P — The point-to-point setting for the port:
◆
Config — The administrator configured P2P setting.
■
Actual – The operational point-to-point status of the LAN segment
■
attached to this interface. This parameter is determined by manual
configuration or by auto-detection.
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| Spanning Tree
C 10
HAPTER
Configuring STP Port Settings