On a Definition object -- a network-control policy definition that governs discovery-protocol and uplink-failure behavior for a vNIC/vHBA template or service profile -- cucsNwctrlDefinitionUplinkFailAction is an enumerated state/type value reporting what action (such as link-down) UCS Manager takes on this policy's vNICs when the uplink fails. An admin reads this enumeration because it distinguishes between the specific operating modes or states that a Definition instance can be in, which affects how UCS Manager and connected hosts behave. For example, an admin diagnosing behavior on a particular Definition instance would check cucsNwctrlDefinitionUplinkFailAction to see which specific mode or state is currently configured or active.