Backup and Recovery

Philosophies

3-2-1

The principles of the 3-2-1 backup philosophy help to effectively backup data. That data can be recovered in a worst-case scenario where one or two backups may be corrupted or lost.

  • 3 = Keep three backups of a file.

  • 2 = Keep two backups on different storage devices.

  • 1 = Keep one backup in a remote location.

These are the absolute minimum. More backups can be used as needed. [1]

Btrfs

grub-btrfs

The Antynea/grub-btrfs project will automatically generate GRUB entries for every Btrfs snapshot.

Install:

$ git clone https://github.com/Antynea/grub-btrfs.git
$ cd grub-btrfs
$ sudo make install

It can now be configured. Change the GRUB submenu entry name to an agnostic name (by default, it will say “ArchLinux Snapshots”).

$ sudo ${EDITOR} /etc/default/grub-btrfs/config
GRUB_BTRFS_SUBMENUNAME="Btrfs Snapshots"

Now, whenever the GRUB configuration is re-generated, the Btrfs snapshots will be shown on boot.

$ sudo grub-mkconfig -o /boot/grub/grub.cfg

dd

Compressed Backup

It is possible to create a backup of a storage device while compressing the live streamed data.

  • XZ for maximum compression. [8]

    • Create a backup using XZ compression.

      $ sudo dd if=/dev/<DEVICE> status=progress | xz --stdout > <BACKUP_FILE>.img.xz"

    • Restore a backup using XZ decompression.

      $ xz --decompress --stdout <BACKUP_FILE>.img.xz | sudo dd of=/dev/<DEVICE> status=progress"

  • Zstandard for a balance of compression and speed. [9]

    • Create a backup using Zstandard compression.

      $ sudo dd if=/dev/<DEVICE> status=progress | zstd > <BACKUP_FILE>.img.zst

    • Restore a backup using XZ decompression.

      $ zstdcat <BACKUP_FILE>.img.zst | sudo dd of=/dev/<DEVICE> status=progress

Clonezilla

Introduction

Clonezilla is a live Debian ISO that can do a fast and efficient backup of a drive. It takes into account file systems, sector sizes, and partition alignment. It is recommended to use this over dd. [2][3] However, Clonezilla does not support going from a large drive to a small drive. [7]

Drive to Drive

Clonezilla can clone from one drive to another.

  • Download Clonezilla.

  • Use dd on Linux or Rufus on Windows to flash the Clonezilla ISO to an external drive.

  • For backing up a Windows >= 8 drive, first fully shutdown the operating system. Fast Startup is enabled by default which makes it so the “Shutdown” button in Windows acts more like a hibernate state. [4]

    C:\Windows\system32>shutdown /s /f /t 0

  • Boot into Clonezilla. Select all of the default options until you get to the “Select mode:” screen.

  • Select the “device-device” mode.

  • Select “Beginner mode”.

  • Select “disk_to_local_disk local_disk_to_local_disk_clone”.

  • Choose the source/original storage device.

  • Choose the destination/new storage device.

  • Select “-sfsck” to skip checking the file system.

  • Select “-k0 Use the partition table from the source disk”. [5]

  • Select what to do after the clone is complete: “choose” when done, “true” for getting a command prompt, “reboot”, or “shutdown”.

After the drive has been cloned, it is required to resize and/or move the partitions to take advantage of the increased space. [6]

History

Bibliography

  1. “The 3-2-1 Backup Rule – An Efficient Data Protection Strategy.” NAKIVO. November 13, 2017. Accessed September 5, 2020. https://www.nakivo.com/blog/3-2-1-backup-rule-efficient-data-protection-strategy/

  2. “[SOLVED] dd or clonezilla.” Ubuntu Forums. May 3, 2018. Accessed July 30, 2023. https://ubuntuforums.org/showthread.php?t=2390792

  3. “Why is Clonezilla faster than dd?” Server Fault. January 8, 2021. Accessed July 30, 2023. https://serverfault.com/questions/495723/why-is-clonezilla-faster-than-dd

  4. “How to Fully Shutdown Windows?” Vovsoft. July 30, 2023. March 15, 2023. https://vovsoft.com/blog/how-to-fully-shutdown-windows/

  5. “[Solved] Clonzilla Does Not See New SSD.” Linux Mint Forums. June 26, 2021. Accessed July 30, 2023. https://forums.linuxmint.com/viewtopic.php?t=351705

  6. “How to clone a Windows 10 installation to new drive using Clonezilla.” Pureinfotech. June 29, 2023. Accessed July 30, 2023. https://pureinfotech.com/clone-windows-10-drive-clonezilla/

  7. “DRBL/Clonezilla FAQ/Q&A.” DRBL. July 1, 2023. Accessed July 30, 2023. https://drbl.org/fine-print.php?path=./faq/2_System/25_restore_larger_disk_to_smaller_one.faq#25_restore_larger_disk_to_smaller_one.faq

  8. “Backup to and Restore from a Disk Image in Linux.” COMFILE Technology’s Documentation Library. March 6, 2024. Accessed July 19, 2024. http://comfilewiki.co.kr/en/doku.php?id=cupc:backup_restore:index

  9. “compressing and decompressing dd image - zstd instead of gzip.” Unix & Linux Stack Exchange. September 10, 2022. Accessed July 19, 2024. https://unix.stackexchange.com/questions/492773/compressing-and-decompressing-dd-image-zstd-instead-of-gzip