DISTRIBUTED CONTROL PROTOCOL FOR HIGH AVAILABILITY IN MULTI-NODE STORAGE CLUSTER

摘要

A distributed control protocol dynamically establishes high availability (HA) partner relationships for nodes in a cluster. A HA partner relationship may be established by copying (mirroring) information maintained in a non-volatile random access memory (N VRAM) of a node over a HA interconnect to the NVRAM of a partner node in the cluster. The distributed control protocol leverages a Cluster Liveliness and Availability Manager (CLAM) utility of a storage operating system executing on the nodes to rebalance NVRAM mirroring and alter HA partner relationships of the nodes in the cluster. The CLAM utility is configured to maintain various cluster related issues, such as CLAM quorum events, addition or subtraction of a node in the cluster and other changes in configuration of the cluster. Notably, the CLAM utility is an event based manager that implements the control protocol to keep the nodes informed of any cluster changes through event generation and propagation.