3Com Switch 4210 9-Port, Configuration Manual

Page: 175 / 567

Configuring Guard Functions 173
Perform the mCheck operation in system view
Perform the mCheck operation in Ethernet port view
Configuration Example # Perform the mCheck operation on Ethernet 1/0/1.
1 Perform this configuration in system view
<4210> system-view
[4210] stp interface Ethernet1/0/1 mcheck
2 Perform this configuration in Ethernet port view
<4210> system-view
[4210] interface Ethernet1/0/1
[4210-Ethernet1/0/1] stp mcheck
Configuring Guard
Functions
Introduction The following guard functions are available on an MSTP-enabled switch: BPDU
guard, root guard, loop guard, TC-BPDU attack guard, and BPDU drop.
BPDU guard
Normally, the access ports of the devices operating on the access layer are directly
connected to terminals (such as PCs) or file servers. These ports are usually
configured as edge ports to achieve rapid transition. But they resume non-edge
ports automatically upon receiving configuration BPDUs, which causes spanning
tree recalculation and network topology jitter.
Normally, no configuration BPDU will reach edge ports. But malicious users can
attack a network by sending configuration BPDUs deliberately to edge ports to
cause network jitter. You can prevent this type of attacks by utilizing the BPDU
guard function. With this function enabled on a switch, the switch shuts down the
edge ports that receive configuration BPDUs and then reports these cases to the
administrator. Ports shut down in this way can only be restored by the
administrator.
Table 128 Perform the mCheck operation in system view
Operation Command Description
Enter system view system-view -
Perform the mCheck
operation stp [ interface interface-list ]
mcheck
Required
Table 129 Perform the mCheck operation in Ethernet port view
Operation Command Description
Enter system view system-view -
Enter Ethernet port view interface interface-type
interface-number
-
Perform the mCheck
operation stp mcheck Required