506CHAPTER 13: VLAN MANAGEMENT

Figure 261 Switches Connected by 802.1Q Tagged Links

Primary and Secondary IP interfaces

Some 3Com Layer 3 switches allow multiple IP interfaces to be created for one VLAN. To support this, these Layer 3 switches have the concept of primary and secondary IP interfaces. Primary and secondary IP interfaces determine how the switch processes broadcast and multicast traffic that arrives on a VLAN with multiple IP interfaces.

Take for example a broadcast packet arriving on VLAN 10, which has a primary interface of 158.101.68.254/255.255.255.0 and a secondary of 158.101.69.254/255.255.255.0. If the source address of the packet was on the 158.101.69.0 network, the agent receives the packet on the 158.101.69.254 interface. But there may be times where a packet may

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HP Network Direr Software Products manual Primary and Secondary IP interfaces, Switches Connected by 802.1Q Tagged Links