A backup is a copy of data created to ensure information persistence in the event of software failures, hardware malfunctions, or human errors. Unlike an archive, which stores inactive data for long-term retention, a backup is designed for the rapid restoration of active production environments.
How it works
The process involves copying files, databases, or full disk images to external drives, cloud storage, or tape libraries. Primary strategies include: full backup (copying all data), incremental (changes since the last backup operation), and differential (changes since the last full backup).
Backups are implemented in server infrastructures to protect PostgreSQL, MySQL databases, and file systems. The frequency of backup creation is defined by RPO (Recovery Point Objective) and RTO (Recovery Time Objective) metrics.
The 3-2-1 rule is the industry standard: maintain at least 3 copies of data, store them on 2 different media types, and keep 1 copy off-site. According to data center statistics, the probability of simultaneous failure of two independent disk arrays is near zero, proving the effectiveness of distributed backup storage.