Configuring Mac Address Table - Zte ZXR10 5900 Series User Manual

Dynamic MAC addresses in the MAC address table are learned
by the switch. The procedure of switch learning MAC address
is as follows:
Switch analyzes the source MAC address and VLANID (for ex-
ample, MAC1+VID1) once it receives a data frame on a port.
If judging the MAC address to be valid and learnable, the switch
checks MAC1+VID1 in its MAC address table. If the entry is not
found, the address is added to the MAC address table, other-
wise the entry is updated.
Note:
i. MAC address learning is to learn the source MAC address
of received data frames, not the destination MAC address.
ii. MAC address learning applies to unicast addresses only, not
to broadcast or multicast addresses.
2. MAC Address Aging
The size of the MAC address table is limited, so a MAC address
aging mechanism is provided for effective resource utility of
the MAC address table.
A switch considers a device that has got offline or is not in
communication when it fails to receive any data frame from
that device for a certain time period (set aging time), that is, it
does not receive any data frame from its source MAC address
as that of device's MAC address.
Then the switch deletes that MAC address of the device from
its MAC address table and updates the MAC address table.
MAC address aging applies to dynamic MAC addresses only.
3. Manual Addition and Deletion
An entry can be added to the MAC address table of a switch with
a configuration command when the network is relatively stable
and device is connected to a fixed switch port. Configuration
can take place for dynamic, static or permanent MAC address.
Configuring static or permanent MAC addresses can prevent
MAC spoofing attacks.
MAC address can be deleted with the MAC address deletion
command. Deleting command of ZXR10 5900/5200 can
forcibly delete a dynamically learned MAC address.
Configuring MAC Address
Table
MAC address table of switch can run normally with the default con-
figuration. But some appropriate configuration on MAC address
table can improve the network stability.
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Chapter 5 MAC Address Table Configuration
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