Using the Layer 2 View

Overview

You can use the Layer 2 view of the Device List window to view information about your switches and what is connected to them. With the Layer 2 view, you can answer the following questions:

  • What switch port is this computer connected to?
  • What computers are connected to that switch port?
  • How are these two switches connected?
NOTE: Layer 2 features are experimental.

What Layer 2 Processing Does

Intermapper periodically scans all switches on maps where Layer 2 is enabled (see the Layer 2 pane of the Map Settings window). It collects information on which devices are attached to which ports, what other switches are present, and places the resulting information into the Endpoints pane.

Intermapper Layer 2 uses device MAC addresses to identify devices. It looks through the forwarding databases of the switches to identify the ports where devices connect. The Layer 2 process also looks through ARP tables and other sources of data to map the MAC addresses to IP addresses, to collect DNS names, VLANs, and other information, locating each device as precisely as it can.

When Layer 2 passes the connection information back to the map, automatically showing the connection of each device on the map to the proper port on the switch.

To use Intermapper's Layer 2 scanning:

  1. In the Server Settings window, enable Layer 2 scanning.
  2. Enable Layer 2 in the Map Settings window or in the Layer 2-Enabled Maps window (available in the Server Settings > Layer 2 pane for any map containing switches you want to include during Layer 2 scanning.

To use the Layer 2 connection information to make connections on the map automatically, select Enable Layer 2 scan for this map from the Layer 2 pane of the Map Settings window.

NOTE: The Layer 2 View is disabled when the following occurs:
  • Layer 2 scanning not enabled in the Server Settings > Layer 2 window.
  • The scanning is enabled, but the user is not an administrator.
  • The scanning is enabled, but the user is not an administrator and not a member of the FullLayer2Access group. (A member of this group can access the Layer 2 View without having other administrator privileges. The group is not created automatically; you must create it and add users to it.)

Viewing Layer 2 Information

Layer 2 information is shown in a sub-view of the global Device List Window, available from the Window menu.

To open the Layer 2 view:

  1. From the Window menu, select Device List. The Device List window is displayed.
  2. From the Device List window, click . The Layer 2 window is displayed.

Alternatively, do the following:

  • Right-click a device on a map and click Show in > Layer 2 from the Context menu.

  • Select a device on a map and click Show in > Layer 2 from the Monitor menu.

    NOTE: The Show in > Layer 2 command is available only when Layer 2 scanning is enabled for the map.