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Parameters
dynamic: Specifies dynamic MAC address entries.
static: Specifies static MAC address entries.
blackhole: Specifies blackhole MAC address entries. Packets whose source or destination MAC
addresses match blackhole MAC address entries are dropped.
multiport: Specifies multiport unicast MAC address entries. A frame whose destination MAC
address matches a multiport unicast MAC address entry is sent out of multiple ports.
mac-address: Specifies a MAC address in the format of H-H-H, excluding multicast and all-zero
MAC addresses. When entering a MAC address, you can omit the leading zeros in each H section.
For example, enter f-e2-1 for 000f-00e2-0001.
vlan vlan-id: Specifies an existing VLAN to which the interface belongs. The value range for the
vlan-id argument is 1 to 4094.
interface interface-type interface-number: Specifies an outgoing interface by its type and number.
interface interface-list: Specifies interfaces in the format of { interface-type interface-number [ to
interface-type interface-number ] } &<1-n>. The interface can only be a Layer 2 Ethernet interface or
Layer 2 aggregate interface. &<1-4> specifies that you can configure up to 4 interfaces or interface
ranges.
Usage guidelines
Typically, the device automatically builds the MAC address table by learning the source MAC
addresses of incoming frames on each interface. However, you can manually configure static MAC
address entries. For a MAC address, a manually configured static entry takes precedence over a
dynamically learned entry. To improve the security for the user device connected to an interface,
manually configure a static entry to bind the user device to the interface. Then, the frames destined
for the user device (for example, Host A) are always sent out of the interface. Other hosts using the
forged MAC address of Host A cannot obtain the frames destined for Host A.
To drop frames with the specified source MAC addresses or destination MAC addresses, you can
configure blackhole MAC address entries.
To send frames with a specific destination MAC address out of multiple ports, configure a multiport
unicast MAC address entry. When you execute this command for the first time, the command adds a
MAC address entry. When you execute the command again with the same MAC address and VLAN
but with different interfaces, this command adds the specified interfaces for this entry.
A static or blackhole MAC address entry can overwrite a dynamic MAC address entry, but not vice
versa.
If you execute the undo mac-address command without specifying any parameters, this command
deletes all unicast MAC address entries and static multicast MAC address entries.
You can delete all the MAC address entries (including unicast MAC address entries and static
multicast MAC address entries) of a specified VLAN. You can also delete only one type (dynamic,
static, blackhole, or multiport unicast) of MAC address entries. You can single out an interface and
delete the corresponding unicast MAC address entries, but not the corresponding static multicast
MAC address entries.
The MAC address entry configuration cannot survive a reboot unless you save it. The dynamic MAC
address entries, however, are lost upon reboot whether or not you save the configuration.
Examples
# Add a static entry for MAC address 000f-e201-0101. Then, all frames that are destined for this
MAC address are sent out of interface GigabitEthernet 1/0/1, which belongs to VLAN 2.
<Sysname> system-view
[Sysname] mac-address static 000f-e201-0101 interface gigabitethernet 1/0/1 vlan 2
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