30.1.0/24F0/3F0/23750SWITCHF0/1WLCSSID “USERNET”SSID “GUEST”APVLAN...

172. - CCNA WIRELESS OFFICIAL EXAM CERTIFICATION GUIDE PART 19 POTX 172. - CCNA WIRELESS OFFICIAL EXAM CERTIFICATION GUIDE PART 19 POTX 172. - CCNA WIRELESS OFFICIAL EXAM CERTIFICATION GUIDE PART 19 POTX
CCNA WIRELESS OFFICIAL EXAM CERTIFICATION GUIDE PART 19 POTX
172.30.1.0/24F0/3F0/23750SwitchF0/1WLCSSID “USERNET”SSID “GUEST”APVLAN 20VLAN 10

Figure 9-11 VLAN Topology

Step 3. Save the configuration.

Step 4. Configure trunk ports where necessary.

Using the standard topology in Figure 9-11, the first step is to create the VLANs that you

will use. In the figure, VLANs 10 and 20 are in use. You will then assign a VLAN to an in-

terface on the switch or configure the proper interface as a trunk. You should begin with

the VLAN configuration.

Creating VLANs

VLANs are identified by a number ranging from 1 to 4094 on most switch platforms.

VLANs ranging from 1 to 1001 are stored in a VLAN database. VLANs 1002 through

1005 are reserved for Token Ring and FDDI VLANs and are created by default. You can-

not remove them. VLANs greater than 1005 are considered extended-range VLANs and

are not stored in the VLAN database.

Follow these guidelines when defining VLANs:

■

The switch supports 1005 VLANs in VTP client, server, and transparent modes.

Note: VTP is the VLAN Trunk Protocol, designed to maintain consistency of VLANs in a

network. This topic is beyond the scope of this book and will not be discussed. For more

information on VLANs, see Interconnecting Cisco Network Devices, Part 2 (ICND2):

(CCNA Exam 640-802 and ICND Exam 640-816), 3rd Edition, published by Cisco Press.

■

Normal-range VLANs are identified with a number between 1 and 1001. VLAN

numbers 1002 through 1005 are reserved for Token Ring and FDDI VLANs.

1

■

VLAN configuration for VLANs 1 to 1005 is always saved in the VLAN database. If

the VTP mode is transparent, VTP and VLAN configuration are also saved in the

switch running configuration file.

1

■

The switch also supports VLAN IDs 1006 through 4094 in VTP transparent mode

(VTP disabled). These are extended-range VLANs, and configuration options are lim-

ited. Extended-range VLANs are not saved in the VLAN database.

■

Before you can create a VLAN, the switch must be in VTP server mode or VTP trans-

parent mode. If the switch is a VTP server, you must define a VTP domain, or VTP

will not function.

1

Cisco switches have default VLAN values. VLAN 1 is assigned to each interface, and

the port is configured to dynamically determine if trunking is being used.

To add a VLAN to a switch, use the command vlan vlan-id. You can see this in Table 9-2.

Table 9-2 VLAN Creation Commands

Key Topic

Command Action

vlan vlan-id Enter a VLAN ID, and enter config-vlan mode. Enter a new VLAN ID to cre-

ate a VLAN, or enter an existing VLAN ID to modify that VLAN.

name

(Optional) Enter a name for the VLAN. If no name is entered for the VLAN,

the default is to append the VLAN ID with leading zeros to the word VLAN.

vlan-name

The steps to create a VLAN are as follows:

Step 1. Access global configuration mode using the configure terminal command.

Step 2. Create the VLAN using the vlan command.

Step 3. Optionally give the VLAN a name using the name command.

Step 4. Exit to privileged EXEC mode using the end command.

You can verify your work using the show vlan command.

In Example 9-1, VLANs 10 and 20 are created on the 3750 switch seen in Figure 9-11.

These VLANs are used for the trunk interfaces between the AP and switch, switch and

controller, and switch and GW router.

Example 9-1 Creating the VLANs

Switch#configure terminalEnter configuration commands, one per line. End with CNTL/Z.Switch(config)#vlan 10Switch(config-vlan)#exitSwitch(config)#vlan 20Switch(config)#endSwitch#