Arrangement for operating a computer cluster

摘要

An arrangement is disclosed for operating a computer cluster distributed over multiple locations using quorum mechanism. The cluster includes interconnected defined system instances. The arrangement includes distributing the cluster configuration to each system instance, and constantly checking system instance connectivity to determine reachable system instances. Each healthy system instance determines a subcluster of itself and all reachable system instances. Information of the distributed cluster configuration is used to calculate a corresponding subcluster configuration. Subcluster configuration information and the cluster configuration information is used for computing a new quorum decision for the corresponding subcluster, using a location quorum function considering proportions of connected locations containing reachable system instances, and weights of the reachable system instances in the locations. Workload placement decisions are made based on the new quorum granting permission to place workload to system instances in a specific subcluster, or refusing the permission, whenever the subcluster changes.

主权项

1. An apparatus for operating a computer cluster distributed over multiple locations using quorum mechanism, wherein said cluster (C) comprises a plurality of interconnected defined system instances running on a physical or virtual hardware, wherein each system instance in said cluster (C) runs a distributed cluster manager (P), wherein a cluster configuration (CC) comprises location information about each system instance defined in said cluster (C) and is distributed to each defined system instance, the apparatus comprising one or more of hardware and software, the software stored on one or more non-transitory computer readable media, the apparatus comprising:
a membership service (M) that constantly checks connectivity among said system instances defined in said cluster (C) to determine reachable system instances, wherein said membership service (M) in each healthy system instance determines a subcluster (SCx) comprising said corresponding healthy system instance and all reachable system instances said healthy system instance is connected to, using information of said distributed cluster configuration (CC), and that calculates corresponding subcluster configuration (SCC(SCx)) comprising location information about each system instance of said subcluster (SCx); a location aware quorum computation service (Q) in said healthy system instance that uses said subcluster configuration (SCC(SCx)) information and said cluster configuration (CC) information for computing a new quorum decision for said corresponding subcluster (SCx) said healthy system instance is member of, using a location quorum function (LQF) considering proportions of connected locations containing reachable system instances, and weights of said reachable system instances in said locations; and a workload placement software service (P) in said healthy system instance that makes workload placement decisions based on a computed new quorum granting permission to place workload to system instances in a specific subcluster (SCx), or refusing said permission, whenever said subcluster (SCx) changes.