Lantech LGS-2816C-RPS, Руководство пользователя

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C
HAPTER
4
| Configuring the Switch
Configure SNMP
P
ARAMETERS
These parameters are displayed on the Spanning Tree Protocol Status
page:

Port Status – It displays the current state of a port. We
cannot manually set it because it displays the status only.
There are three possible states. ( according to 802.1w
specification).

DISCARDING state indicates that this port can neither
forward packets nor contribute learning knowledge.
N
OTE
:
Three other states (Disable state, BLOCKING state and
LISTENING state) defined in the 802.1D specification are now all
represented as DISCARDING state.

LEARNING state indicates this port can now contribute its
learning knowledge but cannot forward packets still.

FORWARDING state indicates this port can both contribute
its learning knowledge and forward packets normally.

Path Cost Status - It is the contribution value of the path
through this port to Root Bridge. STP algorithm determines a
best path to Root Bridge by calculating the sum of path cost
contributed by all ports on this path. A port with a smaller
path cost value would become the Root Port more possibly.

Configured Path Cost - The range is 0 – 200,000,000. In the
switch, if path cost is set to be zero, the STP will get the
recommended value resulted from auto-negotiation of the link
accordingly and display this value in the field of Path Cost
Status. Otherwise, it may show the value that the
administrator set up in Configured Path Cost and Path Cost
Status.

802.1w RSTP recommended value: (Valid range: 1 –
200,000,000).
10 Mbps: 2,000,000,
100 Mbps: 200,000 and 1 Gbps : 20,000.
Defautle is 0

Priority - Priority here means Port Priority. Port Priority and
Port Number are mixed to form the Port ID. Port IDs are often
compared in order to determine which port of a bridge would
become the Root Port. The range is 0 – 240. Default is 128.

Admin Edge Port - If user selects ―Yes‖, this port will be an
edge port. An Edge Port is a port connected to a device that
knows nothing about STP or RSTP. Usually, the connected
device is an end station. Edge Ports will immediately transit to
forwarding state and skip the listening and learning state
because the edge ports cannot create bridging loops in the
network. This will expedite the convergence. When the link on
the edge port toggles, the STP topology keeps unchanged.