Get off Hadoop deliberately, before the hardware refresh forces the decision

Overview

Most Hadoop clusters running today are on borrowed time — the distribution vendor changed, the hardware is due for refresh, and the operational expertise has been leaving for years. AceMQ plans and executes the migration to object storage with open table formats, translating workloads rather than lifting them into a shape that will need migrating again.

Challenge

A ten-year-old Hadoop estate holds thousands of Hive tables, MapReduce jobs whose authors have left, Oozie coordinators nobody fully understands, and Kerberos-backed authorization expressed in Ranger policies that do not map cleanly to cloud IAM. Nothing can be turned off until its consumers are found, and the consumer list is not written down anywhere. The forcing function is usually a hardware end-of-life date, which leaves less time than the work requires.

Environment

On-premises Hadoop distributions with HDFS, Hive, YARN, MapReduce, Oozie, and Ranger, migrating to cloud object storage with Delta Lake or Iceberg.

Approach

AceMQ starts with dependency discovery from HiveServer2 query logs, HDFS audit logs, and scheduler history to establish what is actually read and by whom — typically a fraction of what exists. Workloads migrate by domain in waves with dual-running validation, MapReduce and Hive queries are translated to Spark SQL rather than emulated, and Ranger policies are rebuilt as catalog grants. Decommissioning is scheduled per domain once consumers confirm cutover.

Solution

• Dependency discovery from HiveServer2 query logs, HDFS audit logs, and Oozie history to identify live versus dormant datasets
• Table format selection and partition redesign for object storage, replacing HDFS-era layouts that assume local disk
• Translation of MapReduce and Hive workloads to Spark SQL, with legacy UDFs ported or replaced rather than wrapped
• Oozie coordinator conversion to Airflow DAGs with dependency semantics preserved
• Ranger and Kerberos authorization rebuilt as catalog-level grants mapped to existing identity groups
• Wave-based cutover with dual-running reconciliation and a per-domain decommissioning schedule

Outcome

Technologies