Bridging Commands
Page 17-8

Bridging Commands

The Bridge Management menu provides several commands that are useful in pinpointing
problems in the network. The commands allow you to lookup specific MAC addresses and
where they were learned, create and view static bridge addresses, view information on
remote trunking stations, view MAC address statistics for a group or a port, or look up infor-
mation on domain mappings. Many times a network problem can be tracked down by view-
ing MAC address information, finding out where it came from, and where it forwards data.
The following sections detail the specific bridging commands that perform these functions.

Displaying Bridge Forwarding Table

You can display the MAC addresses and their forwarding and filtering information for a given
group. The information in the table is used by the transparent bridging function in determin-
ing how to propagate a received frame.
To display the information for a group in the switch follow these steps:
1. Enter the fwt command at the system prompt as follows:
fwt <group number>
where <group number> is the number of the group for which you want to view MAC
addresses. For example, to view MAC addresses for group 2, you would enter:
fwt 2
As a variation of this command, you can enter the fwt command without a group ID. This
will display MAC addresses for the currently selected group in this switch. For informa-
tion on selecting a group, see Selecting a Default Group on page 17-7.
2. Once you have entered the group number you will be prompted for a slot and port, as
shown:
Enter Slot/Interface (return for all ports):
3. Enter the slot and interface (port) number and press <return>. For example, to view MAC
addresses for port 2 on slot 3, enter 3/2 as shown:
Enter Slot/Interface (return for all ports): 3/2
The following screen appears listing the MAC addresses on this port:
Total number of MAC addresses learned for VLAN 2: 8
Non-Canonical Group CAM Last Exp ATM
Sl/If/Srvc/In MAC Address MAC Address T ID Indx S Seen Timer VCI
----------------- ------------------------ ------------------------ -- --------- ------- -- -------- --------- -------
3/1/ Brg/ 1 0020DA:A373B0 00045B:C5CE0D E 2 305A T 11 300
3/1/ Brg/ 1 0020DA:8656F0 00045B:616A0F E 2 3060 T 11 300
3/1/ Brg/ 1 00045B:ED48C0 00045B:2251A1 E 2 3080 T 29 300
3/1/ Brg/ 1 000077:8DDBB9 00045B:65EE22 E 2 3010 T 29 300
3/1/ Brg/ 1 000039:F5520C 0009E4:3ED444 E 2 300E T 35 300
3/1/ Brg/ 1 009027:17F7EB 00045B:2D43EF E 2 3018 T 59 300
3/1/ Brg/ 1 0020DA:0C41E5 00045B:ED48C0 E 2 3078 T 26 300
3/1/ Brg/ 1 0020DA:9645A1 0000EE:B1DB9B E 2 304E T 18 300