Introduction to Hive Table Backup

A Hive table is a logical construct residing on various filesystems such as HDFS, EMRFS, or MapRFS. The Hive metastore holds metadata about your data, which can be accessed directly by other processes. The process of backing up a Hive table is similar to backing up any other files on the filesystem where it is stored.

While there are multiple methods to back up a Hive table, including creating snapshots, exporting data to external storage, and replicating the table, using a dedicated backup and recovery tool can significantly enhance the automation and efficiency of the process. In this article, we will explore best practices for backing up Hive tables using AWS EMR and S3, two powerful tools provided by Amazon Web Services.

Back Up Your Hive Table with AWS EMR

AWS EMR (Elastic MapReduce) offers significant advantages over on-premise Hadoop clusters, making it a preferred choice for many users. The key benefits include:

Scalability and Cost Efficiency: AWS EMR allows you to provision fewer primary/core nodes and more task nodes, providing better elasticity and fault tolerance, especially with the use of spot instances. Automated Management: EMR manages the infrastructure, including the Hadoop and HBase daemons, making it easier to deploy and manage. Data Durability and Availability: S3, used in conjunction with EMRFS, offers 11 nines data durability and 4 nines availability, providing robust data protection.

Following best practices on EMR, it is advisable to store all permanent data on S3 via EMRFS and only use on-cluster HDFS for transient/working data. This configuration not only enhances data durability but also improves the cluster's performance by allowing more resources to be dedicated to processing tasks.

Choosing the Right Metadata Storage

When it comes to storing the metadata for your Hive tables, you have a few options:

Glue Metastore: AWS Glue offers an automated managed service for metastores, providing a convenient and scalable solution. Dedicated RDS Metastore: If you require features not supported by Glue, you can use a dedicated metastore running on an RDS (Relational Database Service) instance.

Both options provide reliable metadata storage, but the choice depends on your specific requirements and the features you need.

Backup Strategies for S3 Storage

S3 is used as the primary storage for your Hive tables due to its high availability and durability. However, you must ensure data integrity to protect against accidental deletes and updates.

AWS Backup Service offers both continuous and periodic backup strategies for S3 buckets. This service provides a robust and automated way to back up your data, reducing the potential for data loss.

For on-prem Hadoop clusters, AWS Backup Agent can be used to back up the cluster to S3. If offloading to the cloud is not an option, consider running a second Hadoop cluster with a higher disk-to-core ratio to ensure data redundancy and availability.

Conclusion

Back up your Hive tables using best practices to ensure data integrity and availability. Whether you are using AWS EMR, S3, or other tools, follow the guidelines provided to protect your data effectively. Regularly review your backup strategy with your AWS support engineer or Technical Account Manager (TAM) to ensure compliance with the latest best practices and optimize your data protection processes.