在华为设备中，
如上图所示的网络拓扑图所示，三台电脑的IP地址分别是 10.1.10.1，10.1.10.2，10.1.10.3
在第一次使用
[sw1-Vlanif1]display mac-address
[sw1-Vlanif1]
会出现没有mac-address这个信息，但是如果
[sw1-Vlanif1]ping 10.1.10.1
[sw1-Vlanif1]ping 10.1.10.2
[sw1-Vlanif1]ping 10.1.10.3
上面这几条命令，就会得到
[sw1-Vlanif1]display mac-address
MAC address table of slot 0:
-------------------------------------------------------------------------------
MAC Address VLAN/ PEVLAN CEVLAN Port Type LSP/LSR-ID
VSI/SI MAC-Tunnel
-------------------------------------------------------------------------------
5489-981c-530a 1 - - GE0/0/1 dynamic 0/-
5489-9806-1761 1 - - GE0/0/2 dynamic 0/-
5489-9857-707b 1 - - GE0/0/3 dynamic 0/-
-------------------------------------------------------------------------------
Total matching items on slot 0 displayed = 3
why
由于mac-address的老化时间为300s，如果对其修改那么又没有了
[sw1]mac-address aging-time 299
修改老化时间为299，从300设置为299
[sw1]display mac-address aging-time
Aging time: 299 seconds
此时
[sw1]display mac-address
[sw1]
[sw1]ping 10.1.10.3
PING 10.1.10.3: 56 data bytes, press CTRL_C to break
Reply from 10.1.10.3: bytes=56 Sequence=1 ttl=128 time=50 ms
Reply from 10.1.10.3: bytes=56 Sequence=2 ttl=128 time=40 ms
Reply from 10.1.10.3: bytes=56 Sequence=3 ttl=128 time=40 ms
Reply from 10.1.10.3: bytes=56 Sequence=4 ttl=128 time=50 ms
Reply from 10.1.10.3: bytes=56 Sequence=5 ttl=128 time=50 ms--- 10.1.10.3 ping statistics ---
5 packet(s) transmitted
5 packet(s) received
0.00% packet loss
round-trip min/avg/max = 40/46/50 ms[sw1]display mac-address
MAC address table of slot 0:
-------------------------------------------------------------------------------
MAC Address VLAN/ PEVLAN CEVLAN Port Type LSP/LSR-ID
VSI/SI MAC-Tunnel
-------------------------------------------------------------------------------
5489-9857-707b 1 - - GE0/0/3 dynamic 0/-
-------------------------------------------------------------------------------
Total matching items on slot 0 displayed = 1