User Guide

508 CHAPTER 13: VLAN MANAGEMENT
Figure 262 VLANs Connected Using an 802.1Q Tagged Link Between Switches
To avoid any VLAN subdivision, it is recommended that all inter-switch
connections are made members of all available VLANs to ensure
connectivity at all times. For example, the connections between Switches
A and B, and between Switches A and C should be 802.1Q tagged and
carrying VLANs 1 and 2 to ensure connectivity.
3Com Network
Director VLAN
Concepts
Discovering VLANs in 3Com Network Director
When you perform a network discovery 3Com Network Director will
retrieve the following information from each supported switch:
■ the textual description of the VLAN
■ the 802.1Q VLAN ID
■ the ports on the device that are tagged members of the VLAN
■ the ports on the device that are untagged members of the VLAN
■ any Layer 3 information associated with the VLAN e.g. IP address and
subnet mask, or protocol type if a non-IP VLAN.
In addition to gathering VLAN information from switches, 3Com Network
Director will also infer the VLAN membership of devices that have no
VLANs configured.