configure VLANs on an Aruba switch

Configuring VLANs on an Aruba switch involves creating VLANs, assigning ports to VLANs, and ensuring that the switch's VLAN interfaces (if needed) are set up properly for inter-VLAN routing, if applicable. Below is a step-by-step guide to configuring VLANs on an Aruba switch, assuming you're working with a typical ArubaOS-Switch (formerly known as ProCurve) switch.

Step-by-Step Guide: Configuring VLANs on an Aruba Switch

1. Access the Switch

To begin configuring the Aruba switch, you need to log in to the switch’s command-line interface (CLI). You can access it through a console cable, SSH, or Telnet, depending on your network setup.

ssh admin@<switch-ip-address>

(Replace <switch-ip-address> with the IP address of your Aruba switch.)

2. Enter Global Configuration Mode

Once logged in, you should be in the user exec mode. Enter privileged exec mode (enable), then proceed to the global configuration mode.

enable
configure terminal

3. Create VLANs

You can create VLANs on the switch using the vlan command. Below, we’ll create VLANs 10, 20, and 30 as an example.

vlan 10
   name "Sales"
vlan 20
   name "HR"
vlan 30
   name "Engineering"

In this case:

• VLAN 10 is named Sales.
• VLAN 20 is named HR.
• VLAN 30 is named Engineering.

4. Assign Ports to VLANs

Now that the VLANs are created, you need to assign switch ports to these VLANs. For instance, let's assign ports 1/1/1 and 1/1/2 to VLAN 10 (Sales), ports 1/1/3 and 1/1/4 to VLAN 20 (HR), and ports 1/1/5 and 1/1/6 to VLAN 30 (Engineering).

Use the following commands:

interface 1/1/1
   vlan 10
interface 1/1/2
   vlan 10
interface 1/1/3
   vlan 20
interface 1/1/4
   vlan 20
interface 1/1/5
   vlan 30
interface 1/1/6
   vlan 30

5. Configure Tagged (Trunk) Ports

If you're setting up a trunk link between this switch and another switch or device (e.g., router or another switch), you need to configure trunk ports. Trunk ports allow multiple VLANs to pass over the same physical interface.

For example, let's configure port 1/1/24 as a trunk port carrying VLANs 10, 20, and 30:

interface 1/1/24
   vlan trunk allowed 10,20,30
   vlan trunk native 1   # Optional: Set the native VLAN (usually VLAN 1)

• The vlan trunk allowed command specifies which VLANs are allowed on this trunk port.
• The vlan trunk native command sets the native VLAN (usually VLAN 1 by default, but you can change it as per your requirements).

6. Configure IP Interfaces for Routing (Optional)

If you want to enable inter-VLAN routing (routing between VLANs), you need to configure Layer 3 interfaces on the switch. This is typically done if the Aruba switch has Layer 3 capabilities (such as on the Aruba 2540, Aruba 2930F, or Aruba 5400R series switches).

For example, to configure an IP interface for VLAN 10:

interface vlan 10
   ip address 192.168.10.1 255.255.255.0
   no shutdown

Repeat the process for VLANs 20 and 30, giving them unique IP addresses:

interface vlan 20
   ip address 192.168.20.1 255.255.255.0
   no shutdown

interface vlan 30
   ip address 192.168.30.1 255.255.255.0
   no shutdown

In this example:

• VLAN 10 is assigned the IP address 192.168.10.1 with a subnet mask of 255.255.255.0.
• VLAN 20 is assigned the IP address 192.168.20.1 with a subnet mask of 255.255.255.0.
• VLAN 30 is assigned the IP address 192.168.30.1 with a subnet mask of 255.255.255.0.

7. Verify the VLAN Configuration

After configuring VLANs and assigning ports, you can verify the configuration using the following commands:

View VLAN Information:

show vlan

This will display all VLANs configured on the switch, including VLAN IDs, names, and ports associated with each VLAN.

View the VLAN Assignment on Interfaces:

show interfaces brief

This will show the status of all interfaces, including their VLAN membership.

Verify Trunk Ports:

show interfaces trunk

This will show the trunk ports and which VLANs are allowed on each trunk link.

View Layer 3 Interfaces:

show ip interface brief

This will show the IP addresses and status of Layer 3 interfaces (if configured).

8. Save the Configuration

To save your changes to the switch configuration:

write memory

This command ensures that your configuration is saved and will persist through a reboot.