HP MSR2000/3000/4000 Router Series Layer 2 - LAN Switching Command Reference

Table Of Contents
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A static or blackhole MAC address entry can overwrite a dynamic MAC address entry, but not vice
versa.
If you execute the undo mac-address command without specifying any parameters, this command
deletes all unicast MAC address entries.
You can delete all the MAC address entries of a specified VLAN, or you can delete only a specific type
(dynamic, static, or blackhole) of MAC address entries. You can single out certain interfaces and delete
the corresponding unicast MAC address entries.
The MAC address entries configuration cannot survive a reboot unless you save it. The dynamic MAC
address entries, however, are lost upon reboot regardless of whether you save the configuration.
Examples
# Add a static entry for MAC address 000f-e201-0101. All frames that are destined for this MAC address
are sent out of interface Ethernet 2/1, which belongs to VLAN 2.
<Sysname> system-view
[Sysname] mac-address static 000f-e201-0101 interface ethernet 2/1 vlan 2
Related commands
display mac-address
mac-address (interface view)
mac-address mac-learning enable
Use mac-address mac-learning enable to enable MAC address learning on an interface.
Use undo mac-address mac-learning enable to disable MAC address learning on an interface.
Syntax
mac-address mac-learning enable
undo mac-address mac-learning enable
Default
MAC address learning is enabled.
Views
Layer 2 Ethernet interface view
Predefined user roles
network-admin
Usage guidelines
To prevent the MAC address table from becoming saturated, you can disable MAC address learning.
For example, a number of packets with different source MAC addresses reaching a device can affect the
MAC address table update. You can disable MAC address learning to avoid such attacks, but the
following guidelines apply:
If you disable MAC address learning on an interface, the interface stops learning MAC addresses,
and the device cannot dynamically update the MAC address table.
Because disabling MAC address learning can result in broadcast storms, enable broadcast storm
suppression after you disable MAC address learning on an interface. For more information about
broadcast storm suppression, see Interface Configuration Guide.