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Advanced Data Protection

Snapshots

Snapshots are used to create the entire architectural instance/copy of an application, disk, or system.

  • often used in backup processes to provide rollback points that can restore the system or disk to a specific time
  • assist in backup strategies
    • but are not the same as image backups
    • depend on the original data

Types of Snapshots

  • VM snapshots
    • capture the state of a virtual machine, including its memory, storage, and configuration settings
    • allows administrators to roll back the VM to a previous state
    • e.g., part of VMware vSphere or Microsoft Hyper-V
  • Filesystem snapshots
    • capture the state of a file system at a given moment
    • enables users to:
      • recover accidentally deleted files
      • or restore previous versions of files in case of data corruption
    • e.g., ZFS or Btrfs
  • SAN snapshots
    • are taken at the block-level storage layer within a storage area network
    • e.g., NetApp or Dell EMC storage systems
      • capture the state of the entire storage volume
      • allow for rapid recovery of large datasets and applications

Replication and Journaling

Replication and journaling are data protection methods that ensure data availability and integrity by maintaining multiple copies and tracking changes to data.

Replication involves creating and maintaining exact copies of data on different storage systems or locations.

  • safeguard against data loss by having redundant copies of the data
  • can be utilized to restore the system to its original state
  • e.g., database mirroring
    • maintains primary and secondary mirrored databases

Journaling is a method used by file systems to record changes not yet made to the file system in an object called a journal.

  • records changes to data in a separate, dedicated log
  • can track and monitor data modifications and revert to previous states
  • beneficial for data recovery in system crashes
    • enables the system to
      • identify and undo any incomplete transactions that might have caused inconsistencies
      • or replay transactions that occurred after the full system backup was completed
  • provides greater granularity for restores and greatly minimizes data loss
  • e.g.,
    • file system journaling
      • Journaled File System (JFS)
      • New Technology File System (NTFS)
      • These file systems maintain a record of all changes made to files

Remote journaling creates and maintains a journal of data changes at a separate, remote location.

  • allows for data recovery and ensuring business continuity

SAN replication duplicates data from one SAN to another in real time or near real time, providing redundancy and protection against hardware failures, human errors, or data corruption.

  • involves:
    • synchronous replication
      • which guarantees data consistency
    • asynchronous replication
      • is more cost-effective but slightly less stringent in consistency

VM replication creates and maintains an up-to-date copy of a virtual machine on a separate host or location.

  • ensures that a secondary VM can quickly take over the workload in the event of a primary VM failure or corruption

Encrypting Backups

  • encryption of backups is essential for:
    • data security
      • protection against unauthorized access or theft
      • ensuring that sensitive data remains unreadable
    • privacy
      • protect sensitive customer data, intellectual property, or trade secrets
    • and compliance
      • industries and jurisdictions have regulations that mandate the protection of sensitive data stored in backups

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