There are several requirements for Failover support.
To enable Failover support, a Replication Server must connect to Adaptive Servers that are version 12.0 or later and configured for Failover.
Failover of Replication Server System Databases (RSSDs) and user databases is configured directly through the Adaptive Server.
Failover support responds only to failover of the Adaptive Servers; that is, failover of Replication Servers is not supported.
Adaptive Server is responsible for the RepAgent thread failover and its reconnection to Replication Server after failover/failback.
Each Replication Server configures its own connections.