Configuring VLANs
There is a separate STP domain for each port-based VLAN. Routing occurs independently across port-based VLANs or STP domains. You can define each end of each backbone link as a separate tagged port-based VLAN. Routing will occur independently across the port-based VLANs. Because each port-based VLAN’s STP domain is a single point-to-point backbone connection, you are guaranteed to never have an STP loop. STP will never block the virtual interfaces within the tagged port-based VLAN, and you will have a fully routed backbone.
Assigning a Different VLAN ID to the Default VLAN
When you enable port-based VLANs, all ports in the system are added to the default VLAN. By default, the default VLAN ID is “VLAN 1". The default VLAN is not configurable. If you want to use the VLAN ID “VLAN 1" as a configurable VLAN, you can assign a different VLAN ID to the default VLAN.
To reassign the default VLAN to a different VLAN ID, enter the following command:
HP9300(config)# default-vlan-id 4095
Syntax: default-vlan-d <vlan-id>
You must specify a valid VLAN ID that is not already in use. For example, if you have already defined VLAN 10, do not try to use “10” as the new VLAN ID for the default VLAN. Valid VLAN IDs are numbers from 1 – 4095.
NOTE: Changing the default VLAN name does not change the properties of the default VLAN. Changing the name allows you to use the VLAN ID “1” as a configurable VLAN.
Assigning Trunk Group Ports
When a “lead” trunk group port is assigned to a VLAN, all other members of the trunk group are automatically added to that VLAN. A lead port is the first port of a trunk group port range; for example, “1” in 1 – 4 or “5” in 5 – 8. See “Configuring Trunk Groups” in the “Configuring Basic Features” chapter of Book 1.
Configuring Port-Based VLANs
Port-based VLANs allow you to provide separate spanning tree protocol (STP) domains or broadcast domains on a port-by-port basis.
This section describes how to perform the following tasks for port-based VLANs using the CLI:
•Create a VLAN.
•Delete a VLAN.
•Modify a VLAN.
•Assign a higher priority to the VLAN.
•Change a VLAN’s priority.
•Enable or disable STP on the VLAN.
EXAMPLE:
Figure 16.9 shows a simple port-based VLAN configuration using a single HP 6208M-SX switch. All ports within each VLAN are untagged. One untagged port within each VLAN is used to connect the switch to a routing switch (in this example, an HP 6308M-SX) for Layer 3 connectivity between the two port-based VLANs.
