The Adaptive Heartbeat Design of High Availability RAID Dual-Controller

Designing storage systems to provide high availability in the face of failures needs the use of various data protection techniques, such as dual-controller RAID. The failure of RAID controller may cause RAID storage system to fail to respond to ongoing requests and to no longer be available to new requests. Heartbeat is used to detect controllers whether survival. So, the heartbeat cycle´s impact on the high availability of a dual-controller hot-standby system has become the key of current research. To address the problem of fixed setting heartbeat in building high availability system currently, a self-adaptive heartbeat model of dual-controller, which can adjust heartbeat cycle based on the frequency of data read-write request, is designed to improve the high availability of dual-controller RAID storage system. Based on this model, the high availability stochastic Petri net model of fault detection was established and used to evaluate the effect of the availability. In addition, we define a SHA (self-adaptive heart ability) parameter to scale the ability of system heartbeat cycle to adapt to the environment when high availability system is at a changing environment of read and write requests. The results show that, relatively speaking with fixed configuration, the design can enhance dual controller RAID system high availability.