Here are the detailed steps with commands to configure Cisco ASA Firewall in Active/Standby High Availability (HA) mode:

Step 1: Configure Interface Settings

  • Assign IP addresses to the interfaces:

firewall1(config)# interface <interface_name>
firewall1(config-if)# ip address <ip_address> <subnet_mask>
firewall1(config-if)# no shutdown
firewall2(config)# interface <interface_name>
firewall2(config-if)# ip address <ip_address> <subnet_mask>
firewall2(config-if)# no shutdown

Step 2: Configure Failover Communication

  • Define the interface for failover communication:

firewall1(config)# failover lan interface <interface_name>
firewall1(config)# failover lan unit primary
firewall1(config)# failover key <encryption_key>
firewall2(config)# failover lan interface <interface_name>
firewall2(config)# failover lan unit secondary
firewall2(config)# failover key <encryption_key>

Step 3: Configure Failover Link

  • Define the interface and IP addresses for the failover link:

firewall1(config)# failover interface ip <interface_name> <ip_address> <subnet_mask>
firewall2(config)# failover interface ip <interface_name> <ip_address> <subnet_mask>

Step 4: Enable Failover

  • Enable failover on both firewalls:

firewall1(config)# failover
firewall2(config)# failover

Step 5: Configure Failover Behavior

  • Set the failover behavior for specific interfaces:

firewall1(config)# interface <interface_name>
firewall1(config-if)# failover lan unit primary
firewall2(config)# interface <interface_name>
firewall2(config-if)# failover lan unit secondary

Step 6: Synchronize Configuration

  • Synchronize the configuration from the primary firewall to the secondary firewall:

firewall1# write standby

Step 7: Verify Failover Status

Verify the failover status on both firewalls:

firewall1# show failover
firewall2# show failover

These steps outline the configuration of Cisco ASA Firewall in Active/Standby HA mode. Make sure to customize the commands according to your network requirements and interface configurations. It’s important to test the failover functionality and regularly monitor the HA setup to ensure proper operation.