N8406-023 1Gb Intelligent L3 Switch Command Reference Guide (ISCLI) 27
FDB information commands
The forwarding database (FDB) contains information that maps the media access control (MAC) address of each
known device to the switch port where the device address was learned. The FDB also shows which other ports
have seen frames destined for a particular MAC address.
NOTE: The master forwarding database supports up to 8K MAC address entries on the management
processor (MP) per switch.
Table 18 FDB information commands
show mac-address-table address
<
mac-
address
>
Displays a single database entry by its MAC address. You are
prompted to enter the MAC address of the device.
Enter the MAC address using the format:
xx:xx:xx:xx:xx:xx.
(For example: 08:00:20:12:34:56)
You can also enter the MAC address using the format:
xxxxxxxxxxxx. (For example: 080020123456)
Command mode
:
All
show mac-address-table port
<
port
number
>
Displays all FDB entries for a particular port.
Command mode
:
All
show mac-address-table vlan
<
1-4095
>
Displays all FDB entries on a single VLAN. The range is
1-4095.
Command mode
:
All
show mac-address-table state
{
forward|trunk|unknown
}
Displays all FDB entries that match a particular state.
Command mode
:
All
show mac-address-table
Displays all entries in the Forwarding Database.
Command mode
:
All
Show all FDB information
The following command displays Forwarding Database information:
show mac-address-table
Command mode:
All
MAC address VLAN Port Trnk State
----------------- ---- ---- ---- -----
00:02:01:00:00:00 300 1 TRK
00:02:01:00:00:01 300 23 FWD
00:02:01:00:00:02 300 23 FWD
00:02:01:00:00:03 300 23 FWD
00:02:01:00:00:04 300 23 FWD
00:02:01:00:00:05 300 23 FWD
00:02:01:00:00:06 300 23 FWD
00:02:01:00:00:07 300 23 FWD
00:02:01:00:00:08 300 23 FWD
00:02:01:00:00:09 300 23 FWD
00:02:01:00:00:0a 300 23 FWD
00:02:01:00:00:0b 300 23 FWD
00:02:01:00:00:0c 300 23 FWD
An address that is in the forwarding (FWD) state indicates that the switch has learned it. When in the trunking
(TRK) state, the Trnk field displays the trunk group number. If the state for the port is listed as unknown (UNK), the
MAC address has not yet been learned by the switch, but has only been seen as a destination address. When an
address is in the unknown state, no outbound port is indicated.
Clearing entries from the forwarding database
To delete a static MAC address from the forwarding database (FDB), see the ―Static FDB configuration‖ section in
the ―Configuration Commands‖ chapter.
