Home > Articles > Cisco > CCNA Routing and Switching

VLAN Configuration Fundamentals and Commands

After becoming familiar with basic VLAN concepts, you need to learn how to configure your organization's networks and devices. Sean Wilkins, co-author of CCNA Routing and Switching 200-120 Network Simulator, discusses important concepts and commands you will use in setting up networks and getting devices to talk to each other.
Like this article? We recommend

I hope you have read my previous article on virtual LAN (VLAN) concepts, "Virtual vs. Physical LANs: Device Functionalities," and clearly understand what VLANs do and why they are used. This article picks up at that point, discussing the methods of configuring VLANs on Cisco (IOS) switches.

The first section of this article focuses on the commands used to configure VLANs and their associated parameters. The second section discusses a scenario in which VLANs are used, detailing the configuration commands used to meet the scenario requirements.

A Brief History Lesson: VTP's Effects on VLAN Configuration

Before we get into the commands themselves, let's examine how VLANs have been implemented on Cisco switches historically. Since the lat 1990s, Cisco switches have supported a proprietary protocol that is intended to help engineers configure the same VLANs across multiple switches: the Virtual Trunking Protocol (VTP). For this article, you will not need to know the details of how VTP works, but we will look at how VTP affects how VLANs can be configured.

Cisco's original Catalyst switches supported a single trunking protocol: the Cisco Inter-Switch Link (ISL). Because ISL supported only VLANs from 1–1005, early versions of VTP also supported only those VLANs. This means that when using VTP version 1 or 2 (the default), the only supported VLANs would be from this standard range. This range was further limited by the fact that VLANs 1002–1005 were reserved, leaving only VLANs 1–1001 for user allocations.

The IEEE 802.1Q standard caused a lot of changes. One change related to this conversation is that the standard provided a trunking mechanism that supported up to 4,094 VLANs (minus the reserved ones). This welcome improvement provided additional flexibility to network engineers. However, VTP still didn't support the VLANs from this extended range until version 3, which wasn't released until 2009. This delay gave engineers a considerable amount of time to find—and learn to prefer—VLAN assignment (using the extended range) without using VTP.

How does this history affect how you configure VLANs? While all current Cisco switches support IEEE 802.1Q (some only support IEEE 802.1Q), they still ship with VTP server mode enabled, which means that they will support only the initial standard range of VLANs out of the box. To gain access to the extended range of VLANs, you must first configure VTP version 3, place the switch into VTP transparent mode, or disable VTP completely.

VLAN Configuration Commands

Table 1 lists the base commands used to create a VLAN on a switch.

Table 1

Adding a VLAN Directly and Entering into VLAN Configuration Mode





Enter global configuration mode.

switch#configure terminal


Enter VLAN configuration mode and/or create a VLAN.

switch(config)#vlan vlan-id


Configure a name for the VLAN.

switch(config-vlan)#name name

Table 2 shows another method of creating a VLAN: assigning an interface into a VLAN.

Table 2

Assigning the VLAN to a Switchport (and Possibly Creating a New VLAN)





Enter global configuration mode.

switch#configure terminal


Enter interface configuration mode.

switch(config)#interface interface


Configure the interface into a specific VLAN. (If the VLAN doesn't exist, it will be created.)

switch(config-if)#switchport access vlan vlan-id

On the flipside, use the commands shown in Table 3 to delete a VLAN.

Table 3

Deleting a VLAN





Enter global configuration mode.

switch#configure terminal


Delete a configured VLAN.

If an interface is configured into the VLAN being deleted, it will become inactive and will not be displayed in the output of the show vlan command.

switch(config)#no vlan vlan-id

To verify VLAN assignment, use the command shown in Table 4.

Table 4

Verifying Existing VLANs





Display the current VLANs and their assignments.

switch#show vlan [brief]

Because VTP is configured into server mode by default on most switches (as of this writing), the creation of extended VLANs will fail using either of the methods shown in Tables 1 and 2. Keep in mind that this failure will not occur until you leave VLAN configuration mode, so the command itself will be accepted.

To fix this problem, either the VTP version must be changed to 3, or the VTP mode must be changed to transparent or off. VTP version differences are a bit outside the scope of this article. Table 5 shows only the command to alter the VTP mode.

Table 5

Altering VTP Mode





Enter global configuration mode.

switch#configure terminal


Configure the VTP mode.

switch(config)#vtp mode {server | client | transparent | off}

Scenario: The University School

Suppose you work for a school at a university, and the school is in the process of moving to a different building. In the new building, administrative operations and academic labs will be located on the same floor. In the interest of saving money and time, it has been decided that all of the school's devices will be connected via a single network switch. Since security of the administrative devices is important, the administrative network must be physically or virtually separated from the academic network.

The administrative network devices will be assigned into VLAN 100, and all academic network devices will be assigned into VLAN 200. On the switch, all administrative devices will be connected to switchports Fast Ethernet 0/1–0/12, and all academic devices will be connected to switchports Fast Ethernet 0/13–0/24.

To set up this design, each interface must be configured into its respective VLAN. For purposes of this scenario, we will use the interface range command to assign switchports, as shown in Table 6.

Table 6

VLAN Configuration





Enter global configuration mode.

switch#configure terminal


Create VLAN 100.

switch(config)#vlan 100


Create VLAN 200.

Notice that the configuration mode changed to VLAN configuration mode (config-vlan), but this command is still configured as if the user is in global configuration mode.

switch(config-vlan)#vlan 200


Move into interface configuration mode for switchports Fast Ethernet 0/1–0/12.

switch(config-vlan)#interface range fastethernet0/1-12


Configure the switchports into VLAN 100.

switch(config-if)#switchport access vlan 100


Move into interface configuration mode for the switchports Fast Ethernet 0/13–0/24.

switch(config-if)#interface range fastethernet0/13-24


Configure the switchports into VLAN 200.

switch(config-if)#switchport access vlan 200


Once you understand the essentials, configuring VLANs is not all that complex. Where you can be blindsided is with the caveats of a specific switch mode. Make sure to do your homework on the switch mode before attempting configuration. It is best to know early what you have to configure, instead of finding out when the configuration is actually happening and scheduled to function.

This article covers VLAN configuration basics, but we have addressed only one small piece of a typical VLAN configuration. Different sections of a department typically want to communicate outside their own little part of the world. For that capability, you will need to know about the configuration of a router on a stick (ROAS), multilayer switching, and trunking (IEEE 802.1Q). We will cover those details in later articles.

Pearson IT Certification Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from Pearson IT Certification and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about Pearson IT Certification products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites; develop new products and services; conduct educational research; and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by Adobe Press. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.pearsonitcertification.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020