Assuming there are open connections through an active system's virtual servers and a failover occurs, by default, what happens to the connections.

Without connection mirroring enabled on a virtual server, the standby device has no knowledge of existing connection state when it becomes active. This means all TCP and UDP connections that were open through the previously active device are lost and clients must re-establish them to the newly active BIG-IP.

Connections are not automatically maintained; mirroring must be explicitly enabled on each virtual server for state to carry over.

Persistence mirroring preserves persistence records so that reconnecting clients are sent to the same pool member, but it does not keep the original open connections alive through a failover.

BIG-IP does not distinguish between long-lived and short-lived connections for default failover behavior; all connections are lost regardless of protocol without mirroring.

The newly active BIG-IP does not automatically re-initiate connections on behalf of clients; clients must initiate new connections themselves.