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==== Optional verification of download ====

If you have the equipment for the following verification, you may also download
==== Verification of download ====

You should also download
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A perfect match of that string outrules any incidential damage. A perfect match of that string outrules any incidental damage.

>>> THIS IS WORK In PROGRESS BASED ON MY MESSAGE https://lists.debian.org/debian-live/2018/01/msg00010.html

Downloading Debian Jigdo ISOs by a Debian Live system

This page describes how to use a Debian Live system for downloading large Debian installation ISOs or the full set of DVD sized installation ISOs.

What is Jigdo ?

Jigdo is used by Debian as a method to provide the framework of an ISO 9660 image and a set of Debian package URLs which can be used to fill the gaps in the framework. Result of this filling process is the complete ISO image.

Each ISO image is defined by two Jigdo specific files: *.template contains the compressed framework and checksums of the gap content. *.jigdo contains a compressed translation table from checksum to file path, overall image checksums, and a list of fallback mirror server URLs. The package URLs are composed from a mirror URL and the file path from the list in the *.jigdo file.

The downloading user provides the URL of a mirror server which is tried first for package downloading. Packages which remain missing afterwards get downloaded from the fallback mirror servers.

Link lists to the jigdo files of the current Debian "stable" release ISO images are at the end of the web pages which are linked to by

E.g. at

Obtain a Debian Live medium

If you already have a Debian-based system installed and running, then you do not need the Live system, but may rather hop to paragraph "Install package jigdo-file".

Debian Live is a way to get such a Debian-based system without the need to install it on your non-Debian PC. It is available for 32-bit Intel-or-AMD CPUs and for 64-bit Intel-or-AMD CPUs.

Download Debian Live

A brief overview of Debian Live is given at https://www.debian.org/CD/live/ . If you have a 64-bit Intel or AMD CPU then go to the "amd64" list:

If you have a 32-bit CPU go to "i386" (even if it is made by AMD):

There you see various *.iso files with names of graphical GNU/Linux desktops like "gnome", "kde", "xfce". Let's assume you decide for "xfce" and download by help of your normal operating system:

https://cdimage.debian.org/debian-cd/current-live/amd64/iso-hybrid/debian-live-9.3.0-amd64-xfce.iso

Verification of download

You should also download

https://cdimage.debian.org/debian-cd/current-live/amd64/iso-hybrid/SHA512SUMS
https://cdimage.debian.org/debian-cd/current-live/amd64/iso-hybrid/SHA512SUMS.sign

In file SHA512SUMS is listed

80080716db2fe5e808c7ae771fa560e1306465abfb8d92f1290ec80377150f0aed38d05a9abe425b4548a5d30b03a5f5135b0d158ae819855c6d6ef89b689e44  debian-live-9.3.0-amd64-xfce.iso

This should be compared with the result of shell command

sha512sum debian-live-9.3.0-amd64-xfce.iso

which should give the same long string "8008...9e44".

A perfect match of that string outrules any incidental damage. The authenticity of file SHA512SUMS can be verified by shell command

gpg --keyserver keyring.debian.org --verify SHA512SUMS.sign SHA512SUMS

It must say among other info:

gpg: Good signature from "Debian CD signing key <debian-cd@lists.debian.org>"
...
Primary key fingerprint: DF9B 9C49 EAA9 2984 3258  9D76 DA87 E80D 6294 BE9B

The reported "key fingerprint" must match one of those listed at https://www.debian.org/CD/verify .

Put Debian Live on medium

This image file may either be burned onto a DVD medium, or copied plainly onto a USB stick. For instructions see these four paragraphs of the FAQ:

Be extremely careful not to overwrite your hard disk instead of the USB stick !

Consider to first read from the intended device address and watch the USB stick blinking, before daring to write to that address.

Boot Debian Live

Put the DVD into the drive of your computer or plug the USB stick into a USB socket of your computer. Shut down its operating systen, if running, and power on the computer.

After the machine's firmware issued its usual messages you should soon get to see a menu screen with the first item highlighted. Press the Return key to start it.

For a while you will see a black screen or obscure messages. After 1 or 2 minutes you should see a sparsely populated graphical desktop screen with icons representing your computer's reconizable hard disk filesystems.

Open a shell terminal from the desktop icon to the bottom of the screen.

Open a web browser from desktop icon and go to the URL of this wiki page.

Get access to a writable disk filesystem

>>> XFCE file manager

>>> Command line

>>> ??? any peculiarities of MS-Windows or MacOS disks

In the shell terminal go to the writable download directory:

cd /...mount.path.../...path.in.disk.filesystem...

Install package jigdo-file

At least up to the end of 2017, Debian Live systems do not bring the Jigdo download script out of the box. So shell terminal command jigdo-lite will fail with the message

bash: jigdo-lite: command not found

If it instead says "Jigsaw Download", then go on to the next paragraph.

To get script "jigdo-lite" and its helper programs execute these two commands:

sudo apt-get update
sudo apt-get install jigdo-file

If needed, work around a shortcoming of older jigdo-lite

Older versions of jigdo-lite cannot cope with the "https:" prefix of the current *.jigdo URLs. So if the download procedure shown in the next paragraph fails immediately after entering the *jigdo URL with an error message like

File `https://cdimage.debian.org/debian-cd/current/amd64/jigdo-bd/debian-9.3.0-amd64-BD-1.jigdo' does not exist!

then you need to manually download each *.jigdo and each *.template file of the ISO images which you want to get. E.g.

wget https://cdimage.debian.org/debian-cd/current/amd64/jigdo-bd/debian-9.3.0-amd64-BD-1.jigdo
wget https://cdimage.debian.org/debian-cd/current/amd64/jigdo-bd/debian-9.3.0-amd64-BD-1.template

When jigdo-lite sees the desired files already in the download directory it will go on with asking for other info.

Download one or more ISOs

Execute in the shell terminal:

jigdo-lite

The script will ask three questions: *.jigdo URL, local package repository to scan, and user-chosen mirror URL.

  • jigdo [...]: 

asks for the URL of a *.jigdo file. Like

https://cdimage.debian.org/debian-cd/current/amd64/jigdo-bd/debian-9.3.0-amd64-BD-1.jigdo

This URL will be downloaded if not the file already exists in the current directory.

  • Files to scan: 

should simply get an empty line as input. It asks for a directory where a debain-style repository of packages can be found under the name "pool".

  • Debian mirror [...]: 

asks for the user-chosen URL of a Debian server repository. It should lead to a directory where a repository of packages can be found under the name "pool". The repositories are mirrored worldwide. See for country specific proposals:

In germany, for example, you could pick

http://ftp.de.debian.org/debian/

Now begins automatic package downloading for a time span which depends on the size of the resulting ISO, the bandwidth of the mirror server, and its latency.

If a screensaver with password prompt appears after a while, you can get back the desktop by

  • User: user
  • Password: live

Put the resulting ISOs onto medium

If you are more comfortable with non-GNU/Linux tools, you may instead of the following proposals boot your usual operating system and follow the advise at

Here is how to to it directly by the Debian Live system.

For burning the ISO onto a CD, DVD, or BD medium you may use the pre-installed program xfburn with its task "Burn Image".

Or you may install xorriso by

sudo apt-get install xorriso

and burn the ISO by e.g. this shell command:

xorriso -as cdrecord -v dev=/dev/sr0 -eject stream_recording=on  debian-9.3.0-amd64-BD-1.iso

See output of xorriso -devices for a list of detected /dev/sr devices.

For writing to USB stick do e.g.

cp debian-9.3.0-amd64-BD-1.iso /dev/sdd

where /dev/sdd is the overall device address of the USB stick. Do not pull the stick before the "cp" run has ended.

Be extremely careful not to overwrite your hard disk instead of the USB stick !

Consider to first read from the intended device address (here: /dev/sdc) and watch the USB stick blinking, before daring to write to that address.

About verifying the correctness of the copy-to-medium procedure, see

Afterwards you may delete the *.jigdo, *.template, and *.iso file from the download directory to make room for the next download.

See also: