Backup

Data Backup Management  

Often, backup strategies are inconsistent, poorly documented, and misunderstood. This misunderstanding stems from widespread expectations that backups must exist, must be readily available at a moment’s notice, and must be restored immediately, regardless of size. When backup and DR practices are not documented, management will believe that not only do they exist, but that they will be good, consistent, and that they are current (possibly up to the minute). It is therefore critical to document your organizations backup strategy and practices.

After data has been backed up, some system administrators don't worry about data maintenance. They make the assumption that, once “backed up,” data remains consistent and complete. However, experienced administrators know that databases, and data stored on disk in general, can become corrupted just from sitting on disk. Further risk is introduced when third-party data synchronization components and snapshotting technologies are used.

For this reason, you must adopt in-depth backup strategies for all business-critical data.

Ultimately, you should protect the data according to business demands. However, consistency checking puts additional strain on both infrastructure and personnel. You must scale these resources according to the acceptable level of data loss based on business requirements.

  • Identify Data to Backup
  • Select the Backup Approach
  • Assess Risk and Cost Concerns

Establishing reasonable practices is key to any successful backup and data management effort. First, you must develop practices, document these practices, and ensure that IT personnel follow them. Then, you must understand MTTF and maintain a tolerance.

To achieve the highest level of reasonable data retention and silent failure prevention, consider retaining two copies of the data at two geographically distinct locations. Perform weekly MD5 hash checks on the data primary set and monthly checks of the secondary. You can automate these tests and run them in addition to the initial consistency checks performed when the data was created.

Developing sound backup and data retention procedures facilitates the safety of data, compliance with business needs for point-in-time recovery, and potentially regulatory compliance.

Most database technology includes the ability to restore after a disaster. As such, the performance of the database depends on understanding the way in which logging and backups operate and impact performance.

Improperly configuring backups can result in unanticipated outages and even loss of data if backups are corrupt.