User's Manual

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no spanning-tree bpdufilter
Disables BPDU Filter feature on the interface. It
has no effect on the global configuration.
37.2.5 Configuring Uplink Fast
The characteristic Uplink Fast enables new root ports to rapidly enter the Forwarding state when the
connection between the switch and the root bridge is disconnected.
The Uplink Fast function validates only in SSTP/PVST mode.
In global configuration mode, run command Uplink Fast characteristic:
Command Purpose
spanning-tree uplinkfast
Enables uplink fast feature.
no spanning-tree uplinkfast
Disables Uplink Fast feature.
37.2.6 Configuring Backbone Fast
The Backbone Fast characteristic is a supplement of the Uplink Fast technology. The Uplink Fast technology
makes the redundancy line rapidly work in case the direct connection to the designated switch is disconnected,
while the Backbone Fast technology detects the indirect-link network blackout in the upper-layer network and
boosts the change of the port state.
The backbonefast function validates only in SSTP/PVST mode.
In global configuration mode, run command Backbone Fast characteristic:
Command Purpose
spanning-tree backbonefast
Enables backbone fast feature.
no spanning-tree backbonefast
Disables backbone fast feature.
37.2.7 Configuring Root Guard
The Root Guard attribute can prevent a port from serving as a root port after it receives a higher-priority BPDU.
Root Guard characteristic acts differently somehow in SSTP/PVST and RSTP/MSTP. In SSTP/PVST mode,
Root port is always blocked by Root Guard. In RSTP/MSTP mode, Root port won’t be blocked until receiving
higher level BPDU. A port which formerly plays the Root role will not be blocked.
Use the following command to configure the Root Guard feature in the interface configuration mode:
Command Purpose
spanning-tree guard root
Enables Root Guard feature on the interface.
no spanning-tree guard
Disables root guard and loop guard features on
the interface.
spanning-tree guard none
Disables root guard and loop guard features on