This Article guides you on how to migrate CDH to Azure HDInsight.
Best Practices for Migrating CDH to Azure HDInsight
1. Assess the Existing CDH Cluster
Before migration, perform a detailed assessment of your CDH cluster:
- Identify services in use (HDFS, Hive, Spark, HBase, Kafka, etc.).
- Check cluster size, resource consumption, and data storage patterns.
- Analyze job dependencies, data lineage, and security policies.
- Evaluate third-party integrations and custom configurations.
2. Choose the Right Azure HDInsight Cluster Type
HDInsight offers different cluster types, choose the best fit:
- Apache Spark: For big data analytics workloads.
- Apache Hadoop: For batch processing with Hive & MapReduce.
- Apache HBase: For NoSQL real-time workloads.
- Apache Kafka: For real-time data streaming.
- Interactive Query (LLAP): For fast SQL analytics on Hive.
3. Plan HDFS to Azure Storage Migration
Migrate data from HDFS to Azure Data Lake Storage (ADLS) or Azure Blob Storage:
hdfs dfs -copyToLocal /hdfs-data /local-data
az storage blob upload-batch -d my-container --account-name mystorageaccount -s /local-data
Best Practices:
- Use
DistCp
for large-scale HDFS data migration.
- Leverage Azure Data Box for petabyte-scale data transfers.
- Enable ADLS Gen2 hierarchical namespace for better performance.
4. Migrate Hive Metastore
HDInsight uses an external Hive Metastore (Azure Database for MySQL/PostgreSQL).
- Export CDH Hive Metastore:
mysqldump -u root -p --databases metastore > metastore_backup.sql
- Import into Azure Database for MySQL:
mysql -h azure-mysql-server -u admin -p < metastore_backup.sql
- Configure HDInsight to use the external Metastore:
hive.metastore.uris=thrift://azure-metastore:9083
5. Reconfigure and Migrate Hive Queries
Adjust Hive queries for HDInsight compatibility:
- Convert Hive-managed tables to external tables pointing to ADLS/Blob Storage.
- Update queries to use optimized formats like ORC and Parquet.
- Test queries with HDInsight Interactive Query (LLAP) for better performance.
6. Migrate HBase to Azure HDInsight HBase
Export CDH HBase tables:
hbase snapshot export -snapshot myTable -copy-to hdfs:///hbase-backup
Import into HDInsight HBase:
hbase restore_snapshot myTable
7. Migrate Apache Kafka
Use Kafka MirrorMaker for cross-cluster replication:
bin/kafka-mirror-maker.sh --consumer.config source-cluster.properties \
--producer.config target-cluster.properties --whitelist ".*"
- Ensure partition alignment between CDH Kafka and HDInsight Kafka.
- Verify Kafka security settings (SASL, SSL) for authentication.
8. Migrate Apache Spark Jobs
Convert CDH Spark jobs to run on HDInsight Spark:
- Replace HDFS paths with ADLS paths in job configurations.
- Adjust
spark-defaults.conf
settings to match Azure resources.
- Optimize execution by leveraging Azure Synapse for Spark SQL workloads.
9. Implement Security & Access Control
- Enable Azure AD authentication for HDInsight.
- Use Ranger or Azure Role-Based Access Control (RBAC) for fine-grained access.
- Encrypt data at rest using Azure Storage encryption.
10. Validate Migration and Optimize Performance
- Run test workloads to compare performance between CDH and HDInsight.
- Enable autoscaling for optimized cluster resource allocation.
- Monitor performance using Azure Monitor and HDInsight Metrics.
Summary
Migrating from CDH to Azure HDInsight involves careful planning, data migration, security configuration, and performance tuning. Following these best practices ensures a seamless transition while leveraging Azure’s scalability and managed services.