Cisco Systems N3KC3048TP1GE Configuring the Aging Time for the MAC Table, Procedure, Purpose

Configuring the MAC Address Table

Configuring the Aging Time for the MAC Table

Note You can also configure a static MAC address in interface configuration mode or VLAN configuration mode.

Procedure

Command or Action

Step 1 switch# configure terminal

Step 2 switch(config-)#mac-address-table static mac_address vlan vlan-id{drop interface {type slot/port} port-channel number} [auto-learn]

Purpose

Enters configuration mode.

Specifies a static address to add to the MAC address table.

If you enable the auto-learn option, the switch will update the entry if the same MAC address is seen on a different port.

Step 3	switch(config-)#no mac-address-table static	(Optional)
	mac_address vlan vlan-id	Deletes the static entry from the MAC address
		table.

This example shows how to put a static entry in the MAC address table:

switch# configure terminal

switch(config)# mac-address-table static 12ab.47dd.ff89 vlan 3 interface ethernet 2/1

You can use the mac-address-table static command to assign a static MAC address to a virtual interface.

Configuring the Aging Time for the MAC Table

You can configure the amount of time that an entry (the packet source MAC address and port that packet ingresses) remain in the MAC table. MAC aging time can be configured in either interface configuration mode or in VLAN configuration mode.

Note If the Cisco Nexus 3000 switch is used as a Layer 2 or Layer 3 termination switch, Cisco recommends that you set the mac-address-tableaging-timeto 1800 (higher than the default ARP aging time of 1500 seconds) on all VLANs.

Cisco Nexus 3000 switch does not support per-VLAN cam aging timers.

Procedure

	Command or Action	Purpose
Step 1	switch# configure terminal	Enters global configuration mode.

Step 2 switch(config)# mac-address-tableSpecifies the time before an entry ages out and is discarded aging-timeseconds [vlan vlan_id] from the MAC address table.

	Cisco Nexus 3000 NX-OS Layer 2 Switching Configuration Guide, Release 5.0(3)U3(1)
132	OL-26590-01