In a real network, it is often necessary to access each other across VLANs. People usually choose some methods to achieve mutual access between computers in different VLANs, such as one-arm routing. However, the one-arm routing technology has some limitations in terms of bandwidth and forwarding efficiency, so it is rarely used.
The three-layer switch adds routing function on the basis of the original two-layer switch. At the same time, because the data is not routed through the physical line like the single-arm routing, it solves the problem of bandwidth bottleneck and provides a flexible network design. s solution.
Experimental requirements: Due to the needs of the business system, Company A requires a Huawei Layer 3 switch to implement mutual visits between Department A and Department B. The topology is shown in the figure below
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Configuration process:
1. Configure vlan100 and vlan200 in SW1, and configure the ip gateway address.
[SW3]vlan batch 100 200
[SW3]inter vlan 100
[SW3-Vlanif100]ip add 192.168.100.254 24
[SW3-Vlanif100]qu
[SW3]inter vlan 200
[SW3-Vlanif200]ip add 192.168.200.254 24
[SW3-Vlanif200]qu
2. Configure SW2, divide vlan100 and vlan200, and add the interface to vlan
[SW2]vlan batch 100 200
[SW2]port-group 1
[SW2-port-group-1]group-member Ethernet 0/0/1 to Ethernet 0/0/2
[SW2-port-group-1]port link-type access
[SW2-Ethernet0/0/1]port link-type access
[SW2-Ethernet0/0/2]port link-type access
[SW2-port-group-1]port default vlan 100
[SW2-Ethernet0/0/1]port default vlan 100
[SW2-Ethernet0/0/2]port default vlan 100
[SW2-port-group-1]qu
[SW2-port-group-2]group-member Ethernet 0/0/3 to Ethernet 0/0/4
[SW2-port-group-2]port link-type access
[SW2-Ethernet0/0/3]port link-type access
[SW2-Ethernet0/0/4]port link-type access
[SW2-port-group-2]port default vlan 200
[SW2-Ethernet0/0/3]port default vlan 200
[SW2-Ethernet0/0/4]port default vlan 200
[SW2-port-group-2]qu
3. Configure the interconnection interface of SW1 and SW2 as a trunk interface, and release vlan100 and vlan200
SW1配置GE0/0/1口
[SW3]inter GigabitEthernet 0/0/1
[SW3-GigabitEthernet0/0/1]port link-type trunk
[SW3-GigabitEthernet0/0/1]port trunk allow-pass vlan 100 200
[SW3-GigabitEthernet0/0/1]qu
SW2配置GE0/0/1口
[SW2]inter GigabitEthernet 0/0/1
[SW2-GigabitEthernet0/0/1]port link-type trunk
[SW2-GigabitEthernet0/0/1]port trunk allow-pass vlan 100 200
4. Test
Use PC1 to ping 192.168.200.200/24 of PC2, and the communication can be normal
