Bpdu Filtering; Bpdu Guard - SMC Networks 7824M/VSW - annexe 1 Manual

Management Guide
TigerAccess™ EE
8.3.12.5
8.3.12.6
SMC7824M/VSW

BPDU Filtering

BPDU filtering allows you to avoid transmitting on the ports that are connected to an end
system. If the BPDU Filter feature is enabled on the port, then incoming BPDUs will be fil-
tered and BPDUs will not be sent out of the port.
To enable or disable the BPDU filtering function on the port, use the following command.
Command
spanning-tree port
bpdufilter enable
spanning-tree port
bpdufilter disable
no spanning-tree port PORTS
bpdufilter
By default, it is disabled. The BPDU filter-enabled port acts as if STP is disabled on the
port. This feature can be used for the ports that are usually connected to an end system
or the port that you don't want to receive and send unwanted BPDU packets. Be cautious
about using this feature on STP enabled uplink or trunk port. If the port is removed from
VLAN membership, correspond BPDU filter will be automatically deleted.
To enable or disable the BPDU filtering function on the edge port, use the following com-
mand.
Command
spanning-tree edgeport bpdufil-
ter default
no spanning-tree edgeport
bpdufilter default

BPDU Guard

BPDU guard has been designed to allow network designers to enforce the STP domain
borders and keep the active topology predictable. The devices behind the ports with STP
enabled are not allowed to influence the STP topology. This is achieved by disabling the
port upon receipt of BPDU. This feature prevents Denial of Service (DoS) attack on the
network by permanent STP recalculation. That is caused by the temporary introduction
and subsequent removal of STP devices with low (zero) bridge priority.
To configure BPDU guard in the switch, perform the following procedure.
Step 1
Configure the specific port as edge-port.
Command
spanning-tree port
edgeport enable
Mode
PORTS
Enables a BPDU filtering fuction on specific port.
PORTS
Bridge
Disables a BPDU filtering fuction on specific port.
Mode
Enables a BPDU filtering function by default on all
edge ports.
Bridge
Disables a BPDU filtering function by default on all
edge ports.
Mode
PORTS
Bridge Configures the port as Edge port.
Description
Description
Description
CLI
285