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Hands-on Lab·LPIC-2

A backup you have actually restored

Topic 206 asks for backup operations and for notifying users. This guide takes two snapshots of a directory with rsync --link-dest, proves with inode numbers and du that the second one costs almost nothing, restores it and checks the restore with diff -r - then schedules a real shutdown, reads the file systemd wrote, and cancels it.

201: System Maintenance Guide 28 of 29 Intermediate

One host. The shutdown scheduled on this page is real and is cancelled two commands later, with an hour of margin.
Server NameIP AddressOSRolesCPURAMHDD
LPIC2-A01192.168.0.78Ubuntu 26.04 LTSPrimary service host - BIND, Apache, Samba, Postfix. Topic 204 RAID runs on loop devices; this machine has no spare disk2 Core4 GB50 GB

This guide includes

Use this when you need a backup scheme that keeps several days without storing several copies, or when a maintenance window has to be announced. This matters because a backup that has never been restored is an assumption, and because shutdown does more than one thing depending on the flag.

Before you start

  1. Something worth backing up

  2. The first snapshot

  3. A change, and a second snapshot that costs almost nothing

  4. A backup nobody has restored is not a backup

  5. Telling people before you take it away

  6. Putting the machine back

Official sources