3Com 3800 User Manual page 83

Overview of Virtual LANs 5-5
Figure 5-3 illustrates two VLANs spanning two Switches. On Switch 1,
ports 1–16 are part of VLAN Accounting; ports 17–24 are part of VLAN
Engineering. On Switch 2, ports 1–16 are part of VLAN Accounting;
ports 17–24 are part of VLAN Engineering. VLAN Accounting spans
Switch 1 and Switch 2 by way of a connection between Switch 1 port
11 and Switch 2 port 6. VLAN Engineering spans Switch 1 and Switch
2 by way of a connection between Switch 1 port 19 and Switch 2 port
20.
Accounting Engineering
Switch 1
Switch 2
Figure 5-3 Two port-based VLANs spanning two Switches
Using these steps, you can create multiple VLANs that span multiple
Switches, in a daisy-chained fashion. Each Switch must have a
dedicated port for each VLAN. Each dedicated port must be connected
to a port that is a member of its VLAN on the next Switch.
To avoid the creation of a bridging loop, you must configure the VLANs
prior to cabling the ports.