D-Link DGS-3324SR, User Manual

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xStack DGS/DXS-3300 Series Layer 3 Stackable Gigabit Ethernet Switch User Manual
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It is advisable to define an STP Group to correspond to a VLAN group of ports.
The following fields can be set:
Parameter Description
Unit Choose the Switch ID number of the Switch in the switch stack to be modified.
From/To A consecutive group of ports may be configured starting with the selected port.
External Cost (
0 = Auto)
External Cost - 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).
•
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.
Default port cost: 100Mbps port = 200000. Gigabit port = 20000.
•
value 1-200000000
- Define 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.
Hello Time The time interval between the transmission of configuration messages by the des-
ignated port, to other devices on the bridged LAN, thus stating that the Switch is still
functioning. The user may choose a time between 1 and 10 seconds. The default is
2 seconds. This field is only operable when the Switch is enabled for MSTP.
Migration Setting this parameter as "
yes
" will set the ports to send out BDPU packets to other
bridges, requesting information on their STP setting If the Switch is configured for
RSTP, the port will be capable to migrate from 802.1d STP to 802.1w RSTP. If the
Switch is configured for MSTP, the port is capable of migrating from 802.1d STP to
802.1s MSTP. RSTP and MSTP can coexist with standard STP, however the
benefits of RSTP and MSTP are not realized on a port where an 802.1d network
connects to an 802.1w or 802.1s enabled network. Migration should be set as yes
on ports connected to network stations or segments that are capable of being
upgraded to 802.1w RSTP or 802.1s MSTP on all or some portion of the segment.
Edge Choosing the true parameter designates the port as an edge port. Edge ports
cannot create loops, however an edge port can lose edge port status if a topology
change creates a potential for a loop. An edge port normally should not receive
BPDU packets. If a BPDU packet is received, it automatically loses edge port
status. Choosing the false parameter indicates that the port does not have edge
port status.
P2P Choosing the
True
parameter indicates a point-to-point (P2P) shared link. P2P ports
are similar to edge ports, however they are restricted in that a P2P port must
operate in full duplex. Like edge ports, P2P ports transition to a forwarding state
rapidly thus benefiting from RSTP. A p2p value of
false
indicates that the port
cannot have p2p status.
Auto
allows the port to have p2p status whenever possible
and operate as if the p2p status were true. If the port cannot maintain this status,
(for example if the port is forced to half-duplex operation) the p2p status changes to
operate as if the p2p value were
False
. The default setting for this parameter is
True
.
State This drop-down menu allows the user to enable or disable STP for the selected
group of ports. The default is
Enabled
.
Click Apply to implement changes made.