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The Number Limitation Function of MAC and IP in Port, VLAN Configuration
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extent. When malicious users frequently do MAC or ARP cheating, it will be easy for them
to fill the MAC and ARP list entries of the switch, causing successful DOS attacks.
To summer up, it is very meaningful to develop the number limitation function of MAC
and IP in port, VLAN. Switch can control the number of MAC address of ports and the
number ARP, ND list entry of ports and VLAN through configuration commands.
Limiting the number of dynamic MAC and IP of ports:
1. Limiting the number of dynamic MAC. If the number of dynamically learnt MAC
address by the switch is already larger than or equal with the max number of dynamic
MAC address, then shutdown the MAC study function on this port, otherwise, the port can
continue its study.
2. Limiting the number of dynamic IP. If the number of dynamically learnt ARP and ND
by the switch is already larger than or equal with the max number of dynamic ARP and ND,
then shutdown the ARP and ND study function of this port, otherwise, the port can
continue its study.
Limiting the number of MAC, ARP and ND of interfaces:
1. Limiting the number of dynamic MAC. If the number of dynamically learnt MAC
address by the VLAN of the switch is already larger than or equal with the max number of
dynamic MAC address, then shutdown the MAC study function of all the ports in this
VLAN, otherwise, all the ports in this VLAN can continue their study (except special ports).
2. Limiting the number of dynamic IP. If the number of dynamically learnt ARP and ND
by the switch is already larger than or equal with the max number of dynamic ARP and ND,
then the VLAN will not study any new ARP or ND, otherwise, the study can be continued.
48.2
The Number Limitation Function of MAC and IP in
Port, VLAN Configuration Task Sequence
1. Enable the number limitation function of MAC and IP on ports
2. Enable the number limitation function of MAC and IP in VLAN
3. Configure the timeout value of querying dynamic MAC
4. Configure the violation mode of ports
5. Display and debug the relative information of number limitation of MAC and IP on ports