Failover resource record sets only: Among resource record sets that have the same combination of DNS name and type, a value that
indicates whether the current resource record set is a primary or secondary resource record set. A failover set may contain at most one
resource record set marked as primary and one resource record set marked as secondary. A resource record set marked as primary will be
returned if any of the following are true: (1) an associated health check is passing, (2) if the resource record set is an alias with the
evaluate target health and at least one target resource record set is healthy, (3) both the primary and secondary resource record set are
failing health checks or (4) there is no secondary resource record set. A secondary resource record set will be returned if: (1) the primary
is failing a health check and either the secondary is passing a health check or has no associated health check, or (2) there is no primary
resource record set. Valid values: PRIMARY | SECONDARY
Constraints:

C# |
public string Failover { get; set; }