Technical Documentation

show bridge mac-table

Syntax

Release Information

Command introduced in Junos OS Release 8.4.

Description

(MX Series routers only) Display Layer 2 MAC address information.

Options

none: Display all learned Layer 2 MAC address information.
brief | count | detail | extensive: (Optional) Display the specified level of output.
bridge-domain (all | bridge-domain-name): (Optional) Display learned Layer 2 MAC addresses for all bridging domains or for the specified bridging domain.
global-count: (Optional) Display the total number of learned Layer 2 MAC addresses on the system.
instance instance-name: (Optional) Display learned Layer 2 MAC addresses for the specified routing instance.
interface interface-name: (Optional) Display learned Layer 2 MAC addresses for the specified interface.
mac-address: (Optional) Display the specified learned Layer 2 MAC address information.
vlan-id (all-vlan | vlan-id): (Optional) Display learned Layer 2 MAC addresses for all VLANs or for the specified VLAN.

Additional Information

When Layer 2 protocol tunneling is enabled, the tunneling MAC address 01:00:0c:cd:cd:d0 is installed in the MAC table. When the Cisco Discovery Protocol (CDP), Spanning Tree Protocol (STP), or VLAN Trunk Protocol (VTP) is configured for Layer 2 protocol tunneling on an interface, the corresponding protocol MAC address is installed in the MAC table.

Required Privilege Level

view

List of Sample Output

show bridge mac-table
show bridge mac-table brief
show brief mac-table count
show bridge mac-table detail

Output Fields

Table 1 describes the output fields for the show bridge mac-table command. Output fields are listed in the approximate order in which they appear.

Table 1: show bridge mac-table Output fields

Field Name	Field Description
Routing instance	Name of the routing instance.
Bridging domain	Name of the bridging domain.
MAC address	MAC address or addresses learned on a logical interface.
MAC flags	Status of MAC address learning properties for each interface: S—Static MAC address is configured. D—Dynamic MAC address is configured. SE—MAC accounting is enabled. NM—Non-configured MAC.
Logical interface	Name of the logical interface.
MAC count	Number of MAC addresses learned on the specific routing instance or interface.
Learning interface	Name of the logical interface on which the MAC address was learned.
Learning VLAN	VLAN ID of the routing instance or bridge domain in which the MAC address was learned.
Layer 2 flags	Debugging flags signifying that the MAC address is present in various lists.
Epoch	Spanning Tree Protocol epoch number identifying when the MAC address was learned. Used for debugging.
Sequence number	Sequence number assigned to this MAC address. Used for debugging.
Learning mask	Mask of the Packet Forwarding Engines where this MAC address was learned. Used for debugging.
IPC generation	Creation time of the logical interface when this MAC address was learned. Used for debugging.

Sample Output

show bridge mac-table

user@host> show bridge mac-table

MAC flags (S -static MAC, D -dynamic MAC,
           SE -Statistics enabled, NM -Non configured MAC)

Routing instance : vs1
 Bridging domain : vlan100, VLAN : 100
   Learning  MAC                 MAC      Logical
   VLAN      address             flags    interface 
             00:00:00:19:1c:db   D        ge-11/0/3.0          
             00:00:00:59:3a:2f   D        xe-10/2/0.100

show bridge mac-table brief

user@host> show bridge mac-table brief

MAC flags (S -static MAC, D -dynamic MAC,
           SE -Statistics enabled, NM -Non configured MAC)

Routing instance : vs1
 Bridging domain : vlan100, VLAN : 100
   Learning  MAC                 MAC      Logical
   VLAN      address             flags    interface 
             00:00:00:19:1c:db   D        ge-11/0/3.0          
             00:00:00:59:3a:2f   D        xe-10/2/0.100

show brief mac-table count

user@host> show bridge mac-table count

2 MAC address learned in routing instance vs1 bridge domain vlan100

  MAC address count per interface within routing instance:
    Logical interface        MAC count
    ge-11/0/3.0                      1
    ge-11/1/4.100                    0
    ge-11/1/1.100                    0
    ge-11/1/0.100                    0
    xe-10/2/0.100                    1
    xe-10/0/0.100                    0

  MAC address count per learn VLAN within routing instance:
    Learn VLAN ID            MAC count
                0                    2

0 MAC address learned in routing instance vs1 bridge domain vlan200

  MAC address count per interface within routing instance:
    Logical interface        MAC count
    ge-11/1/0.200                    0
    ge-11/1/1.200                    0
    ge-11/1/4.200                    0
    xe-10/0/0.200                    0
    xe-10/2/0.200                    0

  MAC address count per learn VLAN within routing instance:
    Learn VLAN ID            MAC count
                0                    0

show bridge mac-table detail

user@host> show bridge mac-table detail

MAC address: 00:00:00:19:1c:db
  Routing instance: vs1
   Bridging domain: vlan100
   Learning interface: ge-11/0/3.0     Learning VLAN: 0    
   Layer 2 flags: in_ifd, in_ifl, in_vlan, kernel
   Epoch: 4                            Sequence number: 0     
   Learning mask: 0x800                IPC generation: 0     

MAC address: 00:00:00:59:3a:2f
  Routing instance: vs1
   Bridging domain: vlan100
   Learning interface: xe-10/2/0.100   Learning VLAN: 0    
   Layer 2 flags: in_ifd, in_ifl, in_vlan, kernel
   Epoch: 7                            Sequence number: 0     
   Learning mask: 0x400                IPC generation: 0