1. A method of managing a failure of a critical high availability (HA) component, the method comprising the steps of: a computer identifying a plurality of critical HA components of a HA system; the computer receiving and assigning categories to the plurality of critical HA components; the computer receiving and assigning weights to the categories; the computer obtaining a current value indicating a performance of a critical HA component included in the plurality of critical HA components, the current value obtained by periodically monitoring the plurality of critical HA components; the computer receiving a reference value for the performance of the critical HA component; the computer determining a deviation between the current value and the reference value; based on the deviation, the computer determining the critical HA component has failed; and based in part on the failed critical HA component, the categories, and the weights, the computer determining a health index in real-time, the health index indicating in part how much the critical HA component having failed affects a measure of health of the HA system.