Tag: distributed databases

  • A Modern Database Backup and Recovery Checklist

    A Modern Database Backup and Recovery Checklist

    Do you have single points of failure? How do you handle deduplication? These questions and more need consideration when you’re dealing with database backup and recovery.

    Enterprises are quickly onboarding next-generation, mission-critical applications such as eCommerce, artificial intelligence, machine learning and Internet of Things (IoT) on non-relational databases and distributed local storage. However, as organizations move these applications to scalable databases because they are easier to deploy, always available and cost-effective, they also need a robust and scalable backup and recovery solution to protect these modern databases.

    The challenge is that although enterprise adoption of next-generation applications has been rising, the risk of data loss is prevalent. That’s because non-relational databases lack any viable data protection and recovery solution.

    Here is what I mean:

    • Currently, there is a lack of a solution that allows for corrupted data to be removed, replayed and propagated with minimal downtime to customer-facing applications.
    • Reputable studies have concluded that as much as 75 percent of data disasters ultimately leading to downtime are the result of some sort of human error. Because human errors have a big impact on business operations and occur randomly, they cannot be solved by solutions that are offered today, such as native database replication or node-level snapshots.
    • Database replication does not provide point-in-time backup and any-point-in-time recovery, so enterprises cannot go back and fix these errors. In fact, if errors are introduced, the databases’ redundant-node replication can lead to almost immediate corruption across all nodes of the database.

    So, as you begin to explore backup and recovery solution for your next-generation applications, below is a list of items to keep in mind.

    Storage Is No Longer Unified or Shared Storage

    A key architectural transition is occurring where monolithic pools of shared storage are no longer used for next-gen applications and databases. Next-generation databases are scale-out in nature and use commodity storage at a node level, creating a highly distributed storage pool. This distributed storage pool provides both low cost and high performance, but is not conducive to using traditional database backup and recovery tools, which rely on database durability logs (from a shared storage LUN) for a point-in-time backup.

    Eventual Consistency Has a Big Impact on Backup and Recovery

    Next-generation databases are not built around the traditional ACID (Atomicity, Consistency, Isolation, Durability) transaction model. Transactions are a mechanism for guaranteeing these properties; they are a way of grouping related actions together such that as a whole, a group of operations can be atomic, produce consistent results, be isolated from other operations and be durably recorded. Eventual consistency, however, brings forth new challenges to generate a consistent point-in-time view of the database for operational recovery or test/dev needs. Therefore, novel and scale-out data protection technology to address eventual consistency is needed.

    Deduplication Matters at Scale

    With traditional databases, unified or shared database storage, block-level snapshots made image-based recovery and rollback relatively efficient. Distributed storage combined with a scale-out database that commonly involves replication of data rather than joins across tables led to a rapid proliferation of redundant data and increasing storage requirements (three to four copies of every write operation). Effective data reduction at scale is critical to success and economics for effective data protection in this environment.

    Single Points of Failure Do Fail

    Legacy data protection approaches have commonly involved a media server, which presents a choke point for secondary data path and single point of failure. Given the very high ingest rates coupled with the real-time nature of applications deployed on modern scale-out databases, next-generation data protection infrastructure has to be distributed to handle performance (RPO and RTO windows) and resiliency for always-on environments.

    Checklist for Modern Database Data Protection

    • How do you protect your next-generation scale-out databases today? What scenarios of data loss are you worried about?
    • What downtime can your applications or business handle in the event of data corruption?
    • Have you validated backup and recovery for your next-generation databases?
    • Can you prove compliance with regulatory or line-of-business requirements for backup of your critical next-generation infrastructure?
    • Can you recover to a desired or any point in time quickly? What manual effort is required to do this?
    • How much storage is required to store your desired pool of recovery versions?
    • Does your data protection approach scale out with your application and data growth?
    • Can you efficiently refresh your test/dev environment to a smaller or larger cluster size as needed?
    • What happens to your backup solution when a database node fails? Can you still perform backups? How about intermittent network failures?
    • Native formats free you from vendor lock-in and allow for data management services, such as search and analytics on secondary data.
    • Can you recover your data in native format?

    — Jeannie Liou

  • Backup and Recovery for Distributed Databases

    Backup and Recovery for Distributed Databases

    Over the past five years, applications have undergone a paradigm shift. They now require more agility, scalability and availability. The key trends in this era are driven by the use of social platforms, mobile devices and software as a service (SaaS).

    Being able to ingest large amounts of data from various sources and process that data in real-time to deliver contextual information or business insights is a major competitive advantage. To meet these new application requirements, organizations are forced to look beyond traditional relational databases. This has resulted in a slew of new database systems that are distributed and scale-out in nature, can be deployed on commodity hardware and offer tunable consistency-versus-performance trade-offs. It’s important to note that to cater to the agility requirements, database-as-a-service model in cloud is being adopted as well.

    To show just how big the shift to distributed databases is, below is a Keyword Search Trend graph showing the sharp rise in NoSQL search.

    screen-shot-2016-09-27-at-2-03-59-pmThe implication of this is that requirements for data protection have changed forever, driven by this data-centric world (web-scale applications and distributed databases). Organizations are collecting vast amounts of data and seek to drive more value from that data to make better and faster business decisions. Most distributed and cloud databases already provide replication capability and thus satisfy the availability requirements of data protection. However, data protection requirements for scalable point-in-time backup and recovery need to be addressed. Without point-in-time backups, organizations are at substantial risk of losing data due to human error, logical corruption and other operational failures. Traditional backup solutions were built to address the requirements of relational databases that used shared storage and had the ACID transaction model. Unfortunately, they fall well short in addressing the point-in-time backup requirements of distributed databases (local storage, eventual consistency and the elastic nature of infrastructure).

    As database architecture has fundamentally changed to meet new application requirements, data protection needs to be redefined and rearchitected as well. The following are the new requirements for data protection.

    • Take a durable point-in-time backup copy of an eventually consistent database; we call it “versioning” the new paradigm of data protection for this new distributed era: backups to snapshots to replication to copy data management to versioning
    • Minimize time to recover from failures (low RTO)
    • Scale with the growing needs of application
    • Enable easy refresh of test/dev environments for continuous development
    • Provide operational resiliency in event of failures
    • Provide deployment flexibility in public cloud or on-premises data center

    Most organizations are investing in enterprise-grade point-in-time backup and recovery products so they may deploy and scale their next-generation application on distributed databases with confidence. In the next five years, it will be exciting to watch companies redefine the data protection technologies to meet the requirements of next-generation applications.

    — Jeannie Liou