RonR-RPi-image-utils

RonR-RaspberryPi-image-utils

NB scruss is not the author or maintainer of these files (same goes for seamusdemora, who assumed maintenance of this repo from scruss). Please take up any issues or questions in the Image File Utilities thread of the Raspberry Pi Forums site. IOW: This is a file repository only; no support is available here.

Files here are a toolset to create and update a backup of a running RPi OS to a raw image file. The files are copies of those posted on the Raspberry Pi Forums site. The file attachments in that forum don’t seem to be persistent (and are subject to other annoyances imposed by CloudFlare). Consequently, this repo was created by user scruss and is now maintained by seamus, to ensure a current working copy of image-utils is always available through git.

An Overview

I’ve used RonR’s image-utils for several years now, and I’ve become a big fan. In addition to this README, I’ve made a couple of posts on StackExchange re image-utils as a backup solution. Image-utils creates a complete backup of a Raspberry Pi quickly and efficiently; these backups are rendered in the form of an “image file”. The *.img format is ideal as a backup because it’s a complete backup, it’s portable, and it can be loop-mounted. In other words: If your system or SD card or NVME drive becomes corrupted, it can be restored to operation with minimal effort. This restoration requires 3 “ingredients”, and about 5 minutes:

• The raw image backup file (*.img) file - created by image-backup
• A micro SD card (or NVME drive)
• Etcher to write the .img file to the micro-SD card (or NVME drive)

The speed and efficiency of image-backup are especially noteworthy. Because image-backup uses rsync for file copying and syncing, a backup requires only the storage space that is actually used by your system. This is not the same as dd:

1. dd has no way to tell which portions of your drive/SD card are being used versus which portions are not, because dd has no concept of a file. Consequently, a dd backup of a 32 GB SD card requires: …32GB!!
2. Because of this fundamental limitation, dd is “v-e-r-y   s-l-o-w”, and inefficient of space utilization.
3. By comparison, image-backup typically requires a small fraction of the time required for a dd backup, and the image occupies a small fraction of the space required for a dd backup.
4. image-utils can easily and accurately make a backup wile running on a live system; whereas dd will always fail if used to make a backup of a live system. Using dd to make a backup requires the SD card (or NVME) first be un-mounted!
5. The raw image file produced by image-backup can be used in a number of interesting ways - as described by Hiks Gerganov in this post on Baeldung

By comparison, for my systems (Lite; running headless), a backup of a 32GB SD card requires typically a 3-5GB *.img file, and 5-10 minutes; that includes the time for network transfer to a NAS device.

Another efficiency of image-utils is its ability to update an *.img file. In other words, instead of creating an entire new *.img file from scratch, it can update an existing *.img file to incorporate any changes to the filesystems since the last backup. This ability to update further reduces the time required for a backup from 5-10 minutes to (potentially) seconds.

How Do I Use This Repo?

This repo was created to make a current copy of the RPi image-utils toolset available through git. There are many resources available online describing the use of git, so these instructions are minimal. If you have questions, please consult a tutorial of your own choosing. The instructions below reflect using bash from a Raspberry Pi OS terminal or SSH, and assume that git is installed:

1. clone the repo

$ cd && pwd
/home/pi
$ git clone https://github.com/seamusdemora/RonR-RPi-image-utils.git

which should yield (something like) the following results:

$ git clone https://github.com/seamusdemora/RonR-RPi-image-utils.git
Cloning into 'RonR-RPi-image-utils'...
remote: Enumerating objects: 161, done.
remote: Counting objects: 100% (94/94), done.
remote: Compressing objects: 100% (69/69), done.
remote: Total 161 (delta 59), reused 44 (delta 24), pack-reused 67
Receiving objects: 100% (161/161), 57.62 KiB | 1.92 MiB/s, done.
Resolving deltas: 100% (95/95), done.
$

NOTE THAT a new folder named: ‘RonR-RPi-image-utils’ has been created

2. take a look around & verify the ‘git clone’ operation succeeded:

$ ls -la RonR-RPi-image-utils
drwxr-xr-x  2 pi pi  4096 Feb 26 15:29 deprecated
drwxr-xr-x  8 pi pi  4096 Feb 26 15:29 .git
-rw-r--r--  1 pi pi 14084 Feb 26 15:29 image-backup
-rw-r--r--  1 pi pi  1534 Feb 26 15:29 image-check
-rw-r--r--  1 pi pi  3714 Feb 26 15:29 image-chroot
-rw-r--r--  1 pi pi  3399 Feb 26 15:29 image-compare
-rw-r--r--  1 pi pi  3107 Feb 26 15:29 image-info
-rw-r--r--  1 pi pi  1667 Feb 26 15:29 image-mount
-rw-r--r--  1 pi pi  5711 Feb 26 15:29 image-set-partuuid
-rw-r--r--  1 pi pi  4150 Feb 26 15:29 image-shrink
-rw-r--r--  1 pi pi 13740 Feb 26 15:29 README.md
-rw-r--r--  1 pi pi  4086 Feb 26 15:29 README.txt
$

The README.md is this document - the one you’re reading now. The README.txt file contains RonR’s user’s guide for image-utils. The deprecated folder contains an old file discarded by RonR some time ago. The .git folder contains all of the “stuff” that makes git work. And the image-* files are the image-utils files. We’ll discuss what to do with the image-utils files below.

3. keep your clone synced to stay current:

Changes to image-utils are infrequent, but they do happen from time to time. You’ll want to keep your copies updated to match the latest release. Here’s how:

$ cd ~/RonR-RPi-image-utils
$ git config pull.rebase false    # this only needs to be done one time (the first time)
$ git pull                        # all subsequent updates require only this command 

Staging & Usage

Once you’ve cloned the image-utils files to your local git repo, you’ll likely find they are much easier to use by following the very simple install procedure below. Assuming that /usr/local/sbin is in your PATH, using this install procedure makes the utilities easier to use from the command line, or (for example) in a cron job. Here’s how to install:

$ cd
$ sudo install --mode=755 ~/RonR-RPi-image-utils/image-* /usr/local/sbin

Creating vs. Updating .img backups

Refer to the Image File Utilities thread of the Raspberry Pi Forums site for documentation & support. The following is offered only as an illustration/example:

Create the .img backup:

To create a NEW image backup, use the sudo image-backup command; you will be prompted for inputs. The ones I typically use are shown below - immediately following the question mark ?:

$ sudo image-backup

Image file to create? /mnt/SynologyNAS/rpi_share/raspberrypi3b/20230212_Pi3B_imagebackup.img

Initial image file ROOT filesystem size (MB) [2317]? 2400

Added space for incremental updates after shrinking (MB) [0]? 200

Create /mnt/SynologyNAS/rpi_share/raspberrypi3b/20230212_Pi3B_imagebackup.img (y/n)?y

This will take a few minutes depending on your model Pi, the size of your file system & other variables. Upon completion, you should find the image file you specified in the location specified in your answer to the first prompt/question above. This image file contains everything exactly as it was in your file system at the time of the backup. This image file may be written to an SD card, or mount-ed as another file system on your RPi (you can use the image-mount utility for this).

Update an existing .img backup:

To update the image file you have created is even easier; sudo image-backup <IMG_TO_UPDT>, or:

$ sudo image-backup /mnt/SynologyNAS/rpi_share/raspberrypi3b/20230212_Pi3B_imagebackup.img

In other words, simply add the URL of the .img file you wish to update to the basic sudo image-backup command.

Bon Voyage

This concludes the README.md file. Once again, any and all questions re image-utils should be submitted to RonR’s forum page.

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