How to configure VLANs - Access & Trunk Links

Introduction By now we should feel comfortable with terms such as 'VLAN', 'Static & Dynamic VLANs', but this is just the beginning in this complex world. On this page, we will start to slowly expand on these terms by introducing new ones! To begin with, we will take a closer look at the port interfaces on these smart switches and then start moving towards the interfaces connecting to the network backbone where things become slightly more complicated, though do not be alarmed since our detailed and easy to read diagrams are here to ensure the learning process is as enjoyable as possible. VLAN Links - Interfaces When inside the world of VLANs there are two types of interfaces, or if you like, links. These links allow us to ...

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Basic Private VLAN Configuration

Now that the community lab has been equipped with a Catalyst 3560, I have finally been able to write about private VLANs (which are supported only on Catalyst 3560 and higher switches). This article discusses the concept of private VLANs and includes a basic configuration example, with more complex configurations deferred for future articles. Private VLANs were developed to provide the ability to isolate end hosts at layer two. To understand the motivation behind this feature, consider a colocation environment in which the network operator must connect servers belonging to different customers to the Internet. These servers must all be able to reach their first-hop router, but for security reasons, servers belonging to one customer...

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VLANs

Topic: Isolating VM traffic using VLANs Setup: Two Physical Networks: Data Network:  Ethernet network for VM data traffic, which will carry VLAN tagged traffic between VMs.  Your physical switch(es) must be capable of forwarding VLAN tagged traffic and the physical switch ports should be VLAN trunks (Usually this is default behavior.  Configuring your physical switching hardware is beyond the scope of this document). Management Network: This network is not strictly required, but it is a simple way to give the physical host an IP address for remote access, since an IP address cannot be assigned directly to eth0.  Two Physical Hosts: Host1, Host2.  Both hosts are running Open vSwitch.  Each host...

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VLAN Commands

The vlan database Global Configuration mode command enters the VLAN Configuration mode. Syntax vlan database Parameters This command has no arguments or keywords. Default Configuration This command has no default configuration. Command Mode Global Configuration mode User Guidelines There are no user guidelines for this command. Example The following example enters the VLAN database mode. console(config)# vlan database console(config-vlan)# vlan The vlan VLAN Configuration mode command creates a VLAN. Use the no form of this command to delete a VLAN. Syntax vlan vlan-range no vlan vlan-range Parameters ■ vlan-range — Specifies a list of VLAN IDs to be added. Separate nonconsecutive VLAN IDs with a comma and no spaces;...

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