Most large organizations using Accumulo, such as Bloomberg, have two or more data centers distributed geographically. Replication was recently added to Accumulo providing automated eventual consistency between these data centers. On the other hand clients are still left with a need for an automated way to handle a failover from one Accumulo cluster to another. A client application needs the ability to continue processing and operating regardless of what data center.
An operations manager of an Accumulo data center needs the capability to control which Accumulo data center should be used by clients. At any given point in time a data center failover could be triggered by routine maintenance, system upgrade, or any other unforeseen event.
To solve these use cases, the Accumulo Client Failover (ACF) API was developed. This presentation will cover the motivation, design, and use of ACF. We will show how ACF is used by an Accumulo client, and how it can be used alongside an existing third-party Accumulo client library.