Quickly updating a Tails ISO image

... by patching the ISO image file you already have, avoiding downloading the whole new version.

Thanks to the GPG seal published by the Tails project, you will be absolutely sure that the image file thus created is identical to the image published by the Tails project.

Pre-requisites

You MUST already have:

Process

You will download a VCDIFF patchfile, created by me (using the 'xdelta3' software), which describes the differences between the old version of the Tails image you already have, and the new one.

For example a file named 'tails-amd64-6.14.1.iso_to_6.14.2.xdelta3' enables you to patch the Tails AMD 6.14.1 ISO image into a 6.14.2 version. It is useless if you don't already have the file named 'tails-amd64-6.14.1.iso'

Available xdelta3 patchfiles.

Usage

  1. stop Tails (because during this process you will modify the ISO image it uses!)
  2. on a command line (the directory containing your Tails ISO image file must be the current directory), invoke the 6 following commands:
    1. export Tails_PREVIOUS_VERSION=6.14.1 # replace '6.14.1' by the version number of the image file you already have
    2. export Tails_VERSION=6.14.2 # replace '6.14.2' by the version number of the newest version
    3. wget https://tails.net/torrents/files/tails-amd64-${Tails_VERSION}.iso.sig # download the official GPG seal
    4. wget http://makarevitch.com/Tails/upd_xdelta/tails-amd64-${Tails_PREVIOUS_VERSION}.iso_to_${Tails_VERSION}.xdelta3 # download the patchfile
    5. xdelta3 -d -stails-amd64-${Tails_PREVIOUS_VERSION}.iso tails-amd64-${Tails_PREVIOUS_VERSION}.iso_to_${Tails_VERSION}.xdelta3 tails-amd64-${Tails_VERSION}.iso # apply the patchfile
    6. gpg --verify tails-amd64-${Tails_VERSION}.iso.sig # check the new image file
    If it does NOT produce a gpg: Good signature from "Tails developers (offline long-term identity key)" message then something failed (it never happened to me nor to numerous friends) and DO NOT USE the new image.