4.4 HeatWave Cluster Failure and Recovery
HeatWave triggers the recovery process whenever the HeatWave cluster is in an unhealthy state.
The HeatWave cluster status is being monitored regularly and if the cluster does not get a response from the cluster node, the cluster becomes unhealthy due to a node failure and error recovery is triggered.
During the recovery process, HeatWave automatically attempts to bring the node online, and reload data that was previously loaded. HeatWave reloads data from the HeatWave Storage layer, which is created when you enable the HeatWave cluster for the first time. To facilitate recovery, data is persisted to AWS S3 when data is loaded into HeatWave and when data changes is propagated from the DB system to HeatWave. Loading data from AWS S3 is faster because the data does not need to be converted to the HeatWave storage format, as is required when loading data from the DB system.
When you unload a table, the data is removed from HeatWave, and in a background operation, it is removed from AWS S3 too.