Transaction processing apparatus and method

A method of processing a transaction includes processing a transaction workload in a primary process pair on a first node in a cluster of nodes, the processing using at least one stable storage volume for storing a database and another stable storage volume for storing a log, the at least one stable storage volume and the log storage volume forming a log storage group. The method further includes performing checkpointing operations via the network from the primary process pair to a backup process pair while processing the transaction workload, the backup process pair operating on a second node in the cluster of nodes. The method further includes detecting a failure making the first node inoperable or inaccessible, and after detecting the failure, engaging the backup process pair to take over the transaction processing workload of the primary process pair, the backup process pair being configured to operate with the log storage group used by the primary process pair on the failed node.