Switch 7700 Command reference Guide, v2.0

MSTP Configuration Commands 335
port not physically connected with the point-to-point link as connected to such a
link by force.
Related command: stp point-to-point.
Example
Configure Ethernet5/0/3 to be connected to the point-to-point link in system view.
[SW7700]stp interface Ethernet5/0/3 point-to-point force-true
stp interface
root-protection
Syntax
stp interface interface-list root-protection
undo stp interface interface-list root-protection
View
System view
Parameter
interface-list: Ethernet port list, containing multiple Ethernet ports and
expressed as
interface _list = { { interface_type interface_num |
interface_name } [ to { interface_type interface_num | interface_name } ]
}&<1-10>. For detail descriptions of
interface_type, interface_num and
interface_name parameters, refer to the corresponding descriptions in Port
Command Manual. &<1-10> means that the preceding parameters can be
entered up to 10 times.
Description
■ Use the stp interface root-protection command to enable Root
protection on the switch in system view.
■ Use the undo stp interface root-protection command to restore the
default Root protection state.
By default, Root protection is disabled.
In case of configuration error or malicious attack, the legal primary root may
receive the BPDU with a higher priority and then loose its place, which causes
network topology change errors. Due to the illegal change, the traffic supposed to
travel over the high-speed link may be pulled to the low-speed link and congestion
will occur on the network.
Root protection function is used against such problem. The port configured with
Root protection only plays a role of designated port on every instance. Whenever
such port receives a higher-priority BPDU, that is, it is about to turn into
non-designated port, it will be set to listening state and not forward packets any
more (as if the link to the port is disconnected). If the port has not received any
higher-priority BPDU for a certain period of time thereafter, it will resume the
normal state.
Related command: stp root-protection.