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Hosting Operations

Deletes or truncates files

Check Required Files After Restore

You need to confirm every required path exists in the restored sandbox.

Command

BACKUP_ROOT=/srv/backups/site REQUIRED=/srv/backups/site/required-files.txt RESTORE_SANDBOX=/tmp/linuxoneliners-restore/full && rm -rf "$RESTORE_SANDBOX" && mkdir -p "$RESTORE_SANDBOX" && tar -xf "$BACKUP_ROOT/2026-06-25/site.tar" -C "$RESTORE_SANDBOX" && find "$RESTORE_SANDBOX" -type f | sed "s#^$RESTORE_SANDBOX/##" | sort | comm -23 "$REQUIRED" -

Before you run this

System impact: Deletes, truncates, or overwrites data. Requires backup, preview, and exact path review before production use.

When not to use it: Do not rely on this alone for content integrity; pair it with checksums.

Expected output

No output means no required files are missing.

System impact

Deletes or truncates files. The existing restore-sandbox/full directory is removed and recreated, then file paths are compared.

When to use it

Use after sandbox extraction to prove required files are present.

When not to use it

Do not rely on this alone for content integrity; pair it with checksums.

Recovery / rollback

Remove the restore-dr/restore-sandbox/full directory from the example copy. Never point the rm -rf path at production data.

next steps

Related commands

Hosting Operations Deletes data

Diff Restored Config Against Expected

A restored config can exist and still be the wrong config.

BACKUP_ROOT=/srv/backups/site EXPECTED_CONFIG=/srv/backups/site/expected/app/config.yml RESTORE_SANDBOX=/tmp/linuxoneliners-restore/full && rm -rf "$RESTORE_SANDBOX" && mkdir -p "$RESTORE_SANDBOX" && tar -xf "$BACKUP_ROOT/2026-06-25/site.tar" -C "$RESTORE_SANDBOX" && diff -u "$EXPECTED_CONFIG" "$RESTORE_SANDBOX/app/config.yml"
Hosting Operations Deletes data

Extract a Backup Into a Restore Sandbox

A restore drill should write to a sandbox, not production.

BACKUP_ROOT=/srv/backups/site RESTORE_SANDBOX=/tmp/linuxoneliners-restore/full && rm -rf "$RESTORE_SANDBOX" && mkdir -p "$RESTORE_SANDBOX" && tar -xf "$BACKUP_ROOT/2026-06-25/site.tar" -C "$RESTORE_SANDBOX"
Hosting Operations Deletes data

Verify Restored File Checksums

A restore is not validated until the bytes match.

BACKUP_ROOT=/srv/backups/site RESTORE_SANDBOX=/tmp/linuxoneliners-restore/full && rm -rf "$RESTORE_SANDBOX" && mkdir -p "$RESTORE_SANDBOX" && tar -xf "$BACKUP_ROOT/2026-06-25/site.tar" -C "$RESTORE_SANDBOX" && (cd "$RESTORE_SANDBOX" && sha256sum -c CHECKSUMS.sha256)
Hosting Operations Read-only

Find Missing Files in an Old Backup

The fastest failed restore drill is the one that finds missing critical files early.

BACKUP_ROOT=/srv/backups/site REQUIRED=/srv/backups/site/required-files.txt && tar -tf "$BACKUP_ROOT/2026-06-24/site.tar" | sed 's#^./##' | sort | comm -23 "$REQUIRED" -
Hosting Operations Read-only

List Archive Contents Before Extracting

You can inspect a tar backup before it writes a single file.

BACKUP_ROOT=/srv/backups/site && tar -tf "$BACKUP_ROOT/2026-06-25/site.tar" | sed 's#^./##' | sort
Study mapping

Use this as independent command practice: read the notes, predict the output, then compare it with the example before using a real shell.

  • LPIC-1 style command-line practice
  • LFCS style performance-task practice
  • Linux+ style troubleshooting review

Independent study support only. No affiliation, endorsement, exam dumps, or real exam questions.