SPAN Window

This window appears when you choose Port > SPAN on the menu bar. You can also click here to launch it.

Begin by using the Host Name list to select a device whose ports you want to monitor. If you select a Catalyst 2950 or 3550 switch, the window displays a table for defining monitoring sessions. The table has one tab for Catalyst 2950 switches, two for Catalyst 3550 switches. If you select a different type of Catalyst switch, the window displays a table of monitor ports and the ports they monitor.

Follow the steps in one of the following sections, according to the type of switch you selected.

Catalyst 2950 or 3550 Switches

  1. Click the Session 1 tab.
  2. In the Ingress column of the Ingress Source Ports/VLANs table, check the boxes of the ports or VLANs whose outgoing packets you want to monitor.
    You can select multiple ports or multiple VLANs or both.
  3. From the Interface list in the Egress Source Ports area, select an egress source port.
  4. From the Interface list in the Destination Port area, select a destination port. See Monitoring Ports for the requirements for a monitor port.
  5. From the Encapsulation list in the Destination Port area, select an encapsulation type for the destination port.
    Restriction: This option is not available to Catalyst 2950 switches.
  6. Optional for Catalyst 3550 switches: If you checked a trunk port in the table or selected a trunk port from the Interface list in the Egress Source Ports area, you can limit monitoring to certain VLANs by specifying the VLAN IDs in the VLAN Filter field. Separate VLAN IDs with a comma, and use a hyphen to indicate consecutive IDs. For example: 1,3-5
  7. Optional for Catalyst 3550 switches: Click the Session 2 tab and define a second session.
    If you define two sessions, the destination ports must be different ports. Neither can be a source port in the other session.
  8. Click OK to close the SPAN window.

Other Catalyst Switches

  1. Select a port that will be the monitor port.
  2. Click Modify to display the Modify Monitored Ports window.
  3. Complete the window.
  4. Click OK to put your changes in effect and to close the window.
  5. Click OK to close the SPAN window.