Useful tips

How do I tag a VLAN in Linux?

by Rhyley Bryan

How do I tag a VLAN in Linux?

There are two steps required in order to use VLAN tagging on your Linux server:

  1. The first is to hook it up to a switch that has VLAN enabled, connected to a port which is allowed to act as a trunk.
  2. The second thing you’ll need is to create virtual interfaces assigned to the desired VLAN .

What is Linux VLAN?

VLAN is an acronym for Virtual Local Area Network. Several VLANs can co-exist on a single physical switch, which are configured via Linux software and not through hardware interface (you still need to configure actual hardware switch too). VLAN as a name suggest combine multiple LANs at once.

How do you configure VLANs?

To configure VLANs, follow these guidelines:

  1. Create the VLANs.
  2. (Optional) Set the desired VLAN-related configuration for ports.
  3. Assign interfaces to VLANs.
  4. (Optional) Configure VLAN groups on your switch.
  5. (Optional) Configure TV VLAN settings on your switch.

How do I find the VLAN ID in Linux?

You can use tcpdump to disassemble CDP/LLDP packets to find the VLAN number. Traditionally, from a client computer, you cannot tell which vlan you’re in. You can look at an IP address and subnet mask and determine which subnet the IP is in, but not the vlan.

What do I need to know about setting up VLANs?

Choose a valid VLAN number.

  • Choose a private IP address range for devices on that VLAN to use.
  • the administrator assigns a VLAN number to each switch port.
  • Configure routing between VLANs as needed.

    • How can I setup VLAN?

    Create VLAN interface. This would create VLAN interface for VLAN ID 10.

  • Setup new network interface to use the VLAN interface. Probably named ‘ OPT2 ‘.
  • Enable DHCP Server to auto assign IP address. Specify a range of IP address that can be use for assignment (e.g.
  • Setup firewall rules to allow Internet access only.

    • How to add VLAN to a VMware?

    Launch the vSphere application. You can find a shortcut to it on your desktop or in your Start menu.

  • Click on the “Console” tab.
  • Replace the values between parentheses with the appropriate values for your server.
  • Press the “Enter” key on your keyboard.

    • How to create VLAN interface?

    Go to System -> Network and select ‘Create New’. Give a Name to the VLAN interface. Choose the physical interface on which to attach the VLAN. Select ‘Type’ as VLAN. Give the desired VLAN ID. Select ‘Apply’. Go to System -> Network, select the blue arrow to expand the physical port and the VLAN will be displayed.