Quickly updating a Tails ISO image

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

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 official one.

Pre-requisites: you MUST have an old version of the Tails ISO image file, and also an executable xdelta3.

The trick: you download a VCDIFF patchfile, created by me (using xdelta3), which describes the differences between the old version and the new one.

Usage:

  1. stop Tails (you will soon modify the ISO image it uses!)
  2. download the GPG seal (.sig) file of the newest Tails ISO image file
  3. download the adequate xdelta3 patchfile. For example the tails-amd64-6.9.iso_to_6.10.xdelta3 patchfile enables you to patch the Tails AMD 6.9 ISO image into a 6.10 version. It is useless if you don't already have the tails-amd64-6.9.iso file.
  4. patch your image file by invoking: xdelta3 -d -stails-amd64-((Tails_PREVIOUS_VERSION)).iso tails-amd64-((Tails_PREVIOUS_VERSION)).iso_to_((Tails_VERSION)).xdelta3 tails-amd64-((Tails_VERSION)).iso
  5. check the new image file by invoking: gpg --verify tails-amd64-((Tails_VERSION)).iso.sig. If it does NOT produce a gpg: Good signature from "Tails developers (offline long-term identity key)" message then DO NOT USE the new image.