Link Reports and Graphs

With the Link Report and Graphs page, you can:

• Generate link reports.
• Display link graphs.
• Refresh link report information.

Note: You must enable SNMP and set the community string set to "public" to generate reports.

Generating Link Reports

When generating link reports, it is important to understand which device is reporting information to the application. If the link is between two cluster members, both ends of the link provide information for the report. In this case, the member switch that is farthest from the command switch is the controlling switch. If the link is between a cluster member and an edge device, only the member provides information for the report and is the controlling switch. The controlling switch processes the information and reports it to the user interface.

The link report provides port group (and redundant link), VLAN, and network port information. To generate a link report, click Link Report.

The link report displays the following information:

• The IP address and host name of the device at each end of the link.
  The IP address and the host name of the controlling device is displayed in the browser title bar.
• The speed of the link from the perspective of the controlling switch.
  For port groups, the aggregate speed is displayed.
• The duplex setting for each end of the link.
• The port name for each end of the link.
  The list box for each end of the link displays connection information that differentiates a single connection, port group connections, and redundant link connections. In each of these situations, when you select (highlight) a port name in one list box, the port to which it is connected is highlighted in the other list box.
  If the connected port is part of a port group, other port numbers for the group are listed in a shortened form under the Other Ports in Group heading. For example, FastEthernet0/15 is shortened to 0/15.
  If redundant links are present, the STP State message area shows one link in the forwarding state and one link in a blocking state.
• The VLAN IDs.
  A VLAN ID of "Unknown" means that the connected device was not able to supply the information.
• Whether a port has been configured as a network port (unknown unicast packets received on other ports of the VLAN are forwarded only to the network port).
• The linkbeat status.
  The linkbeat determines whether the physical link between two ports is properly connected. A green light means a linkbeat is present. A gray light means no linkbeat is present, a recent problem with the link has occurred, and the presence of that link has been detected through cached CDP information.

Displaying Link Graphs

To generate a graph for the link:

1. From the Link Report and Graphs page, click Graph.
2. From the drop-down list in the upper right corner, select one of the graph types: % Utilization, Total Bytes, Total Packets, or Total Errors.
   The graph displays data for only one end of the link.
   For more information, review the graph descriptions.
   Note: You can change the graph polling interval by clicking User Settings in any view. To make the new settings take effect, close the graph window. Then in Netscape, click Reload (in Internet Explorer, click Refresh) to reload the page. Reopen the graph window. For more information, click Help on the User Settings page.

Refreshing Link Report Information

To refresh link report information, click Link Report.

Graph Descriptions

The following table describes the device and link graphs.