Fault tolerance solution for stateful applications

摘要

A fault tolerance method and system for VMs on a cluster identifies a client state for each client session for those applications. The method replicates the client session onto a primary and a backup VM, and uses a network controller and orchestrator to direct network traffic to the primary VM and to periodically replicate the state onto the backup VM. In case of a VM failure, the method reroutes network traffic of states for which the failed VM serves as a primary to the corresponding backup, and replicates states without a backup after the failure onto another VM to create new backups. The method may be used as part of a method or system implementing the split/merge paradigm.

主权项

1. A method for providing fault tolerance on a virtual machine (VM) cluster, comprising:
maintaining a plurality of VMs in a VM cluster servicing a plurality of client sessions each having a network traffic flow directed to the VM cluster; generating a primary client state and a backup client state for each client session according to a predefined criteria, wherein the primary client state and the backup client state are hosted on separate instances of the VMs in the VM cluster; directing the network traffic flow of each of the client sessions to the VM hosting the primary client state of the client session; detecting a failing VM in the VM cluster; designating the backup client states of the primary client states hosted on the failing VM as new primary client states and directing the network traffic flow of the corresponding client sessions to the VMs hosting the new primary client states; and generating a new backup client state for each of the backup client states hosted on the failing VM and a new backup for each of the new primary client states.