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enabled, the outgoing packets sent by the mirrored port will be
copied to the mirroring port.
LAG:
Displays the LAG number which the port belongs to. The LAG
member can not be selected as the mirrored port or mirroring
port.
Note:
1. The LAG member can not be selected as the mirrored port or mirroring port.
2. A port can not be set as the mirrored port and the mirroring port simultaneously.
3. The Port Mirror function can take effect span the multiple VLANs.
5.1.3 Port Security
MAC Address Table maintains the mapping relationship between the port and the MAC address of
the connected device, which is the base of the packet forwarding. The capacity of MAC Address
Table is fixed. MAC Address Attack is the attack method that the attacker takes to obtain the
network information illegally. The attacker uses tools to generate the cheating MAC address and
quickly occupy the MAC Address Table. When the MAC Address Table is full, the switch will
broadcast the packets to all the ports. At this moment, the attacker can obtain the network
information via various sniffers and attacks. When the MAC Address Table is full, the packets
traffic will flood to all the ports, which results in overload, lower speed, packets drop and even
breakdown of the system.
Port Security is to protect the switch from the malicious MAC Address Attack by limiting the
maximum number of MAC addresses that can be learned on the port. The port with Port Security
feature enabled will learn the MAC address dynamically. When the learned MAC address number
reaches the maximum, the port will stop learning. Thereafter, the other devices with the MAC
address unlearned can not access to the network via this port.
Choose the menu
Switching
→Port→Port Security
to load the following page.
Figure 5-4 Port Security
The following entries are displayed on this screen:
