C
ONFIGURING
THE
S
WITCH
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Command Attributes
The following attributes are read-only and cannot be changed:
•Port Status – Displays current state of this port within the
Spanning Tree:
- Disabled - The port has been disabled by the user or has
failed diagnostics.
- Blocking - Port receives STA configuration messages, but
does not forward packets.
- Listening - Port will leave blocking state due to a topology
change, start transmitting configuration messages, but does
not yet 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.
- Broken - Port is malfunctioning or no link has been
established.
The rules defining port status are:
• A port on a network segment with no other STA compliant
bridging device is always forwarding.
• If two ports of a switch are connected to the same segment
and there is no other STA device attached to this segment,
the port with the smaller ID forwards packets and the ot her
is blocked.
• All ports are blocked when the switch is booted, then some
of them change state to listening, to learning, and then to
forwarding.
•Forward Transitions – The number of times this port has
transitioned from the Learning state to the Forwarding state.