The database host must be reachable from the Database Agent host. The AppDynamics Database Agent normally runs as a standalone process and connects remotely to monitored database instances. Before installation and configuration, the agent host therefore requires network connectivity to each target database over the appropriate database listener port.
This prerequisite includes successful hostname or IP resolution, routing, firewall access, and permission for the agent host to establish a TCP connection to the database service. The Database Agent also requires valid monitoring credentials with the database-specific permissions needed to collect performance statistics, sessions, waits, queries, and other diagnostic data.
Reviewing frequently used primary keys is a database-design activity and is unrelated to agent installation. Adjusting tcp_max_syn_backlog is an operating-system network-tuning task, not a standard Database Agent prerequisite. Dropping system-table keys would be unnecessary and potentially damaging; AppDynamics monitoring does not require destructive changes to database system objects.
Relevant CAAPA Study Guide topics include Database Visibility Architecture, Database Agent Deployment, Network Connectivity Requirements, Database Collector Configuration, Listener Ports, and Monitoring User Permissions.