Cisco ASA Series Cli Configuration Manual page 394

Configuring Active/Active Failover
Note
If you have more than one Active/Active failover pair on the same network, it is possible to have the
same default virtual MAC addresses assigned to the interfaces on one pair as are assigned to the
interfaces of the other pairs because of the way the default virtual MAC addresses are determined. To
avoid having duplicate MAC addresses on your network, make sure you assign each physical interface
a virtual active and standby MAC address for all failover groups.
You can also set the MAC address using other commands or methods, but we recommend using only one
method. If you set the MAC address using multiple methods, the MAC address used depends on many
variables, and might not be predictable.
Use the show interface command to display the MAC address used by an interface.
To configure specific active and standby MAC addresses for an interface, perform the following steps.
Detailed Steps
Command
Step 1
failover group {1 | 2}
Example:
hostname(config)# failover group 1
Step 2
mac address phy_if active_mac standby_mac
Example:
hostname(config-fover-group)# mac address
gigabitethernet1/0 0000.a000.a011
0000.a000.a012
Example
The following partial example shows a possible configuration for a failover group:
hostname(config)# failover group 1
hostname(config-fover-group)# primary
hostname(config-fover-group)# preempt 100
hostname(config-fover-group)# exit
hostname(config)# failover group 2
hostname(config-fover-group)# secondary
hostname(config-fover-group)# preempt 100
hostname(config-fover-group)# mac address gigabitethernet1/0 0000.a000.a011 0000.a000.a012
hostname(config-fover-group)# exit
hostname(config)#
Cisco ASA Series CLI Configuration Guide
1-18
Chapter 1
Purpose
Specifies the failover group.
Specifies the virtual MAC addresses for the active and standby
units.
The phy_if argument is the physical name of the interface, such as
GigabitEthernet1/0. On the ASASM, the phy_if specifies a
VLAN. The active_mac and standby_mac arguments are MAC
addresses in H.H.H format, where H is a 16-bit hexadecimal digit.
For example, the MAC address 00-0C-F1-42-4C-DE would be
entered as 000C.F142.4CDE.
The active_mac address is associated with the active IP address
for the interface, and the standby_mac is associated with the
standby IP address for the interface.
Configuring Active/Active Failover