D-Link xStack DES-3810, Справочное руководство

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xStack
®
DES-3810 Series Layer 3 Managed Ethernet Switch Web UI Reference Guide
101
Tx Hold Count (1-10)
Used to set the maximum number of Hello packets transmitted per interval. The count can
be specified from
1
to
10
. The default is
6
.
Max Hops (6-40)
Used to set the number of hops between devices in a spanning tree region before the
BPDU (bridge protocol data unit) packet sent by the Switch will be discarded. Each switch
on the hop count will reduce the hop count by one until the value reaches zero. The
Switch will then discard the BDPU packet and the information held for the port will age
out. The user may set a hop count from
6
to
40
. The default is
20
.
NNI BPDU Address
Here the user can enter the NNI BPDU Address used. Among the options, the user can
select either
Dot1d
or
Dot1ad
.
Click the
Apply
button to accept the changes made for each individual section.
STP Port Settings
STP can be set up on a port per port basis.
To view the following window, click
L2 Features > Spanning Tree > STP Port Settings
, as shown below:
Figure 5-34 STP Port Settings window
It is advisable to define an STP Group to correspond to a VLAN group of ports.
The fields that can be configured are described below:
Parameter Description
From Port / To Port
Select a range of ports to be configured.
External Cost (0=Auto)
This defines a metric that indicates the relative cost of forwarding packets to the specified
port list. Port cost can be set automatically or as a metric value. The default value is
0
(auto). Setting
0
for the external cost will automatically set the speed for forwarding
packets to the specified port(s) in the list for optimal efficiency. The default port cost for a
100Mbps port is
200000
and the default port cost for a Gigabit port is
20000
. Enter a
value between
1
and
200000000
to determine the External Cost. The lower the number,
the greater the probability the port will be chosen to forward packets.
P2P
Choosing the
True
parameter indicates a point-to-point (P2P) shared link. P2P ports are