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As shown in Figure 1, in the centralized gateway scenario, an enterprise has its own servers in different data centers, Server 1 belongs to VLAN 200, Server 1 2 belongs to VLAN 100 and Server 3 belongs to VLAN 300. Server 1, Server 2 and Server 3 are located in different network segments. Cross-subnet packet forwarding needs to be implemented through a centralized Layer 3 gateway.
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