Patent ID: 8874726

Claim:
A method of servicing an access request using a plurality of replicas of data, the method comprising: determining which of the replicas are available, wherein each of the replicas is included in a list of replicas, and wherein availability of each of the replicas is determined by a controller from the list of replicas, wherein the plurality of replicas include multiple instances of same data on different servers; and selecting one of the replicas for servicing the access request based on which of the replicas are determined as available by the controller using the list of replicas, wherein at least one other replica on the list of replicas is indicated as not available in response to receiving a particular monitoring message from the at least one other replica indicating that the at least one other replica is subject to degraded performance, and wherein monitoring messages received from the plurality of replicas are independent of the access request, wherein each of the monitoring messages is initiated by a corresponding one of the plurality of replicas, and wherein the at least one other replica is indicated in the list of replicas as unavailable based on receipt of the particular monitoring message from the at least one other replica independent of the controller performing an attempt to access or transmit a communication to the at least one other replica.