Appliance Mode Failsafe
If the Firepower 1100, Firepower 2100, or Secure Firewall 3100 in Appliance Mode fails to boot into ASA, it will boot into FXOS failsafe mode. In this mode, FXOS allows minimal configuration to allow diagnosis and recovery of the system. You can configure the management interface with an IP address, DNS, and NTP so you can download and install the ASA image. Only the management interface can be configured in failsafe mode. When you log into FXOS, use the admin user and the ASA enable password that you set previously.
Firepower 2100 Platform mode allows FXOS configuration of chassis functions at all times.
The procedures in this chapter note Appliance Mode and Platform Mode differences.