When creating a new sdconf.rec in the RSA Authentication Manager 8.x Security Console (Access > Authentication Agents > Generate Configuration File > Generate Config File > Download Now to save the AM_Config.zip), the zip file contains two files, an sdconf.rec file and a failover.dat file.
This article explains the failover.dat file.
In order for the RSA Authentication Agent device to communicate with the RSA Authentication Manager server, an agent must be created in the Security Console under Access > Authentication Agents > Add New, completing the required information and saving the agent.
Once the agent is created in Authentication Manager, you must then generate the configuration files by navigating to Access > Authentication Agents > Generate Configuration File > Generate Config File > Download Now.
The failover.dat file allows agent auto-registration to complete when the primary instance is unavailable or separated from the agent host by a firewall that uses Network Address Translation (NAT). The file includes a list of the primary and replica instances, and their alias IP addresses.