Quantum leap cluster upgrade
Tirthankar Das, E.T. Roush, Pramod Nandana · 2009
This paper describes upgrading a running high availability cluster while applications are still running. The whole software stack can be upgraded including operating system, cluster software, volume manager software, application software etc with almost zero downtime. This is done by splitting the cluster in two partitions and upgrading one at a time. This method is different from other split mode upgrade technology by providing the ability to complete all software initialization on the partition running the new software while the older partition hosts service. We call this method Quantum Leap because the cluster leaps from one version of the software to the other.