H3C S3100 Series Operation Manual page 205

Generally, the majority of MAC address entries are created and maintained through MAC address
learning. The following describes the MAC address learning process of a switch:
1) As shown in Figure
User B, the packet from User A comes into the switch on Ethernet 1/0/1. At this time, the switch
records the source MAC address of the packet, that is, the address MAC-A of User A to the MAC
address table of the switch, forming an entry shown in
Figure 1-1 MAC address learning diagram (1)
Figure 1-2 MAC address table entry of the switch (1)
2) After learning the MAC address of User A, the switch starts to forward the packet. Because there is
no MAC address and port information of User B in the existing MAC address table, the switch
forwards the packet to all ports except Ethernet 1/0/1 to ensure that User B can receive the packet.
Figure 1-3 MAC address learning diagram (2)
User B
Eth1/0/4
Eth1/0/1
User A
1-1, User A and User B are both in VLAN 1. When User A communicates with
User C
Eth1/0/3
Figure 1-2.
1-2