An Architecture for Self-healing Autonomous Object Groups

Jgroup/ARM is a middleware for developing and operating dependable distributed Java applications. Jgroup integrates the distributed object model of Java RMI with the object group paradigm, enabling construction of replicated servers that offer dependable services to clients. ARM aims to improve the dependability characteristics of systems through fault treatment, focusing on operational aspects where the gain in terms of improved dependability is likely to be the greatest. ARM offers two core mechanisms: recovery from node, object and network failures and distribution of replicas. ARM identifies failures and reconfigures the system according to its dependability requirements. This paper proposes an enhancement of the ARM framework in which replica placement is performed in a distributed manner, eliminating the need for a centralized manager with global information about all object groups. Instead each autonomous object group handles their own replica placement based on information from nodes. Assuming that multiple objects groups are deployed in the system, this constitutes a distributed replica placement scheme. This scheme enables the implementation of self-healing object groups that can perform fault treatment on themselves. Advantages of the approach: (a) no need to maintain global information about all object groups which is costly and limits scalability, (b) reduced infrastructure complexity, and (c) less communication overhead.