MAC Learning

Disabling dynamic MAC learning prevents a node from learning source and destination MAC addresses.

• To disable MAC learning:

  content_copy zoom_out_map

  [edit vlans vlan-name switch-options interface interface-name]
  user@switch# set no-mac-learning

• To enable MAC learning:

  content_copy zoom_out_map

  [edit vlans vlan-name switch-options interface interface-name]
  user@switch# delete no-mac-learning 
  user@switch# deactivate no-mac-learning

• To verify the status of MAC learning, view the Ethernet MAC learning statistics in operational mode.

  content_copy zoom_out_map

  user@switch> show ethernet-switching table
  Ethernet-switching table: 2 entries, 1 learned
    VLAN              MAC address       Type         Age Interfaces
    default           *                 Flood          - All-members
    default           00:1f:12:39:90:80 Learn         29 xe-/0/0.0
  

Disabling dynamic MAC learning on the device prevents a node from learning source and destination MAC addresses.

• To disable MAC learning on the QFX Series:

  content_copy zoom_out_map

  [edit ethernet-switching-options interfaces interface]
  user@switch# set no-mac-learning

• To enable MAC learning on the QFX Series:

  content_copy zoom_out_map

  [edit ethernet-switching-options interfaces interface]
  user@switch# delete no-mac-learning 
  user@switch# deactivate no-mac-learning

• To verify the status of MAC learning on the QFX Series, view the Ethernet MAC learning statistics in operational mode.

  content_copy zoom_out_map

  user@switch> show ethernet-switching table
  Ethernet-switching table: 2 entries, 1 learned
    VLAN              MAC address       Type         Age Interfaces
    default           *                 Flood          - All-members
    default           00:1f:12:39:90:80 Learn         29 xe-/0/0.0
  

Disabling dynamic MAC learning in a VLAN on a QFX Series product prevents a node from learning source and destination MAC addresses.

• To disable MAC learning in a VLAN:

  content_copy zoom_out_map

  [edit vlans vlan-name]
  user@switch# set no-mac-learning

• To reenable MAC learning in a VLAN, use either of the following two commands:

  content_copy zoom_out_map

  [edit vlans vlan-name]
  user@switch# delete no-mac-learning 
  user@switch# deactivate no-mac-learning

• To verify the status of MAC learning on the QFX series:

  content_copy zoom_out_map

  user@switch> show ethernet-switching table

You can disable MAC learning for all logical interfaces in a specified VLAN, or for a specific logical interface in a VLAN. Disabling dynamic MAC learning prevents the specified interfaces from learning source MAC addresses.

To disable MAC learning for all logical interfaces in a VLAN in a virtual switch, include the no-mac-learning statement at the [edit vlans vlan-name switch-options] hierarchy level:

[edit]
vlans {
    vlan-name {
        domain-type bridge;
        interface interface-name;
        switch-options {
            no-mac-learning;
        }
    }
}

To disable MAC learning for a specific logical interface in a VLAN, include the no-mac-learning statement at the [edit vlans vlan-name switch-options interface interface-name] hierarchy level.

[edit]
vlans {
    vlan-name {
        domain-type bridge;
        interface interface-name;
        switch-options {
            interface interface-name {
                no-mac-learning;
            }
        }
    }
}

You can disable MAC learning for a set of VLANs. Disabling dynamic MAC learning prevents the Layer 2 trunk port associated with the set of VLANs from learning source and destination MAC addresses. When you disable MAC learning, source MAC addresses are not dynamically learned, and any packets sent to these source addresses are flooded into the switch.

To disable MAC learning for a set of VLANs, include the no-mac-learning statement at the [edit switch-options] hierarchy level:

[edit switch-options]
no-mac-learning;