29xx IP address is in the VLAN 1 broadcast domain by default.
  • The switch must be in VTP server mode to create, add, or delete VLANs.
    • The creation of a VLAN on a switch is a very straightforward and simple task. If using a Cisco IOS command based switch, enter the VLAN configuration mode with the privileged EXEC level vlan database command. The steps necessary to create the VLAN are shown below. A VLAN name may also be configured, if necessary. Switch#vlan database
    Switch(vlan)#vlan vlan_number
    Switch(vlan)#exit Upon exiting, the VLAN is applied to the switch. The next step is to assign the VLAN to one or more interfaces: Switch(config)#interface fastethernet 0/9
    Switch(config-if)#switchport access vlan vlan_number Lab Activity Lab Exercise: Configuring Static VLANs This lab is to create a basic switch configuration and verify it and determine the switch firmware version. Lab Activity e-Lab Activity: Configuring Static VLANs In this lab, the students will create a basic switch configuration and verify it.
    Content 8.2 VLAN Configuration 8.2.4 Verifying VLAN configuration A good practice is to verify VLAN configuration by using the show vlan, show vlan brief, or show vlan id id_number commands. The following facts apply to VLANs: Refer to Figure for a list of applicable commands. Figure shows the steps necessary to assign a new VLAN to a port on the Sydney switch. Figures and list the output of the show vlan and show vlan brief commands. Lab Activity Lab Exercise: Verifying VLAN Configurations This lab is to create a basic switch configuration and verify it and determine the switch firmware version. Lab Activity e-Lab Activity: Verifying VLAN Configurations In this lab, the students will create two separate VLANs on the switch.
    Content 8.2 VLAN Configuration 8.2.5 Saving VLAN configuration It is often useful to keep a copy of the VLAN configuration as a text file for backup or auditing purposes. The switch configuration settings may be backed up in the usual way using the copy running-config tftp command. Alternatively, the HyperTerminal capture text feature can be used to store the configuration settings.
    Content 8.2 VLAN Configuration 8.2.6 Deleting VLANs Removing a VLAN from a Cisco IOS command based switch interface is just like removing a command from a router. In Figure , VLAN 300 was created on Fastethernet 0/9 using the interface configuration switchport access vlan 300 command. To remove this VLAN from the interface, simply use the no form of the command. When a VLAN is deleted any ports assigned to that VLAN become inactive. The ports will, however, remain associated with the deleted VLAN until assigned to a new VLAN. Lab Activity Lab Exercise: Deleting VLAN Configurations The purpose of this exercise is to delete VLAN settings. Lab Activity e-Lab Activity: Deleting VLAN Configurations In this lab, the students will create two separate VLANs on the switch.
    Content 8.3 Troubleshooting VLANs 8.3.1 Overview VLANs are now commonplace in campus networks. VLANs give network engineers flexibility in designing and implementing networks. VLANs also enable broadcast containment, security, and geographically disparate communities of interest. However, as with basic LAN switching, problems can occur when VLANs are implemented. This lesson will show some of the more common problems that can occur with VLANs, and it will provide several tools and techniques for troubleshooting. Students completing this lesson should be able to: Web Links VLAN Tech Notes http://www.cisco.com/en/US/tech/ tk389/tk689/tech_tech_notes_ list.html
    Content 8.3 Troubleshooting VLANs 8.3.2 VLAN troubleshooting process It is important to develop a systematic approach for troubleshooting switch related problems. The following steps can assist in isolating a problem on a switched network:
    1. Check the physical indications, such as LED status.
    2. Start with a single configuration on a switch and work outward.
    3. Check the Layer 1 link.
    4. Check the Layer 2 link.
    5. Troubleshoot VLANs that span several switches.
    When troubleshooting, check to see if the problem is a recurring one rather than an isolated fault. Some recurring problems are due to growth in demand for services by workstation ports outpacing the configuration, trunking, or capacity to access server resources. For example, the use of Web technologies and traditional applications, such as file transfer and e-mail, is causing network traffic growth that enterprise networks must handle. Many campus LANs face unpredictable network traffic patterns that result from the combination of intranet traffic, fewer centralized campus server locations, and the increasing use of multicast applications. The old 80/20 rule, which stated that only 20 percent of network traffic went over the backbone, is obsolete. Internal Web browsing now enables users to locate and access information anywhere on the corporate intranet. Traffic patterns are dictated by where the servers are located and not by the physical workgroup configurations with which they happen to be grouped. If a network frequently experiences bottleneck symptoms, like excessive overflows, dropped frames, and retransmissions, there may be too many ports riding on a single trunk or too many requests for global resources and access to intranet servers. Bottleneck symptoms may also occur because a majority of the traffic is being forced to traverse the backbone. Another cause may be that any-to-any access is common, as users draw upon corporate Web-based resources and multimedia applications. In this case, it may be necessary to consider increasing the network resources to meet the growing demand. Web Links VLAN Tech Notes http://www.cisco.com/en/US/tech/
    tk389/tk689/tech_tech_notes_list.html
    Content 8.3 Troubleshooting VLANs 8.3.3 Preventing broadcast storms A broadcast storm occurs when a large number of broadcast packets are received on a port. Forwarding these packets can cause the network to slow down or to time out. Storm control is configured for the switch as a whole, but operates on a per-port basis. Storm control is disabled by default.Prevention of broadcast storms by setting threshold values to high or low discards excessive broadcast, multicast, or unicast MAC traffic. In addition, configuration of values for rising thresholds on a switch will shut the port down. STP problems include broadcast storms, loops, dropped BPDUs and packets. The function of STP is to ensure that no logic loops occur in a network by designating a root bridge. The root bridge is the central point of a spanning-tree configuration that controls how the protocol operates. The location of the root bridge in the extended router and switch is necessary for effective troubleshooting. The show commands on both the router and the switch can display root-bridge information. Configuration of root bridge timers set parameters for forwarding delay or maximum age for STP information. Manually configuring a device as a root bridge is another configuration option. If the extended router and switch network encounters a period of instability, it helps to minimize the STP processes occurring between devices. If it becomes necessary to reduce BPDU traffic, put the timers on the root bridge at their maximum values. Specifically, set the forward delay parameter to the maximum of 30 seconds, and set the max_age