Dell Networking 2048, Справочное руководство

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Spanning Tree Commands
761
Default Configuration
The default port-priority for IEEE STP is 128.
Command Mode
Interface Configuration mode
User Guidelines
If the VLAN parameter is given, the priority is configured only for the
selected VLANs (applies only when pvst or rapid-pvst mode is selected).
Configuration without the VLAN parameter configures the port priority for
RSTP, STP-PV, and RSTP-PV.
If an interface is configured with both the
spanning-tree vlan
vlan-id
port-
priority
priority
command and the spanning-tree port-priority
priority
command, the spanning-tree vlan
vlan-id
port-priority
priority
value is used
as the port priority.
If a VLAN parameter is provided, the VLAN must have been previously
configured or an error is thrown.
An edge port is a port with spanning-tree port-fast enabled. A point-to-point
link is a link configured as full-duplex. Edge-ports and point-to-point links
can directly transition to the forwarding state and do not delay for the
listening and learning stages of spanning-tree. An edge port that receives a
BPDU is no longer considered an edge-port and will utilize the configured
port priority value.
All interfaces and VLANs have 128 as priority value by default. By default,
spanning-tree puts the lowest numbered operationally enabled interface in
the forwarding state and blocks other interfaces. The priority value is used to
override this default behavior. Interfaces with lower port priorities are
preferred for forwarding over interfaces with numerically higher priority
values. STP-PV/RSTP-PV uses the port priority value when the LAN port is
configured as an edge port and uses the VLAN priority value when the
interface is configured as a point-to-point link. MSTP uses the port priority
regardless of whether the port is an edge port or not.
2CSNXXX_SWUM200.book Page 761 Tuesday, December 10, 2013 1:22 PM