Learning term
Backup — Storage and backups
Backup: A separate copy from which lost or damaged data can be restored. This card shows its role in “Storage and backups” and a safe diagnostic path.
Orientation
Backup: A separate copy from which lost or damaged data can be restored. At this level, separate purpose, input, and visible result. Place Backup within Storage and backups before changing settings or files.
Practical use
When data is missing or storage fills up, use `lsblk`, `df -h`, and a restore test to establish utilisation, mounts, and recoverability relevant to Backup. Start in a sandbox with neutral examples. Record the expected state, make one controlled change, and compare status output, application behavior, and logs.
Technical understanding
Backup: A separate copy from which lost or damaged data can be restored. Technically, Backup connects through interfaces, configuration, state, or dependencies. Trace data from input to output and check versions, permissions, networking, storage, and resources separately.
Operations and debugging
When data is missing or storage fills up, use `lsblk`, `df -h`, and a restore test to establish utilisation, mounts, and recoverability relevant to Backup. In production-like operations, use measurable signals, least privilege, reproducible configuration, and a documented rollback. Preserve evidence, isolate the cause, and verify the correction with the same test.
Exercise
Try it safely
When data is missing or storage fills up, use `lsblk`, `df -h`, and a restore test to establish utilisation, mounts, and recoverability relevant to Backup. Open an isolated test environment and run “df -h && du -sh /srv/example-app”. Write down the expected output first, do not alter production data, and record one safe next diagnostic step.
df -h && du -sh /srv/example-appQuick check
Can you explain the purpose, observable state, and most common failure source of Backup — Storage and backups in one sentence each? Which evidence would you preserve before changing anything, and which repeated test would prove that the correction actually worked?