ReAir is a collection of easy-to-use tools for replicating tables and partitions between Hive data warehouses. These tools are targeted at developers that already have some familiarity with operating warehouses based on Hadoop and Hive.
The replication features in ReAir are useful for the following use cases:
When migrating a Hive warehouse, ReAir can be used to copy over existing data to the new warehouse. Because ReAir copies both data and metadata, datasets are ready to query as soon as the copy completes.
While many organizations start out with a single Hive warehouse, they often want better isolation between production and ad hoc workloads. Two isolated Hive warehouses accommodate this need well, and with two warehouses, there is a need to replicate evolving datasets. ReAir can be used to replicate data from one warehouse to another and propagate updates incrementally as they occur.
Lastly, ReAir can be used to replicated datasets to a hot-standby warehouse for fast failover in disaster recovery scenarios.
To accommodate these use cases, ReAir includes both batch and incremental replication tools. Batch replication executes a one-time copy of a list of tables. Incremental replication is a long-running process that copies objects as they are created or changed on the source warehouse.