Re: Using ISO image of installer DVD as repository - How?

[Richard Owlett <rowlett@cloud85.net>]

On 05/31/2019 01:31 PM, Thomas Schmitt wrote:
> Hi,
>
> new idea after googling and finding several examples like Dan Ritter's
> proposal:
>
> Try the "exact path" form of "suite":
>
>    deb file:///home/richard/dvdmount pool/main/
>    deb file:///home/richard/dvdmount pool/contrib/
>
> or the usual form without mentioning (demanding ?) "stretch":
>
>    deb file:///home/richard/dvdmount pool main contrib
>
> Reasoning:
>
> You report this program message:
> > The repository 'file:/home/richard/dvdmount/pool stretch Release'
> > does not have a Release file.
>
> /mnt/iso/pool has "main" and "contrib" but no "stretch".
>
> man 5 sources.list says:
>
>         deb [ options ] uri suite [component1] [component2] [...]
>      [...]
>      can specify an exact path, in which case the components must be omitted
>      and suite must end with a slash (/). This is useful for the case when
>      only a particular sub-section of the archive denoted by the URI is of
>      interest. If suite does not specify an exact path, at least one
>      component must be present.
>
> Suite "stretch" is neither "exact path" nor does it appear in the pool
> tree of DVD 1.
>
> Further for the "exact path" case:
>
>      In the traditional style sources.list format since only one
>      distribution can be specified per line it may be necessary to have
>      multiple lines for the same URI, if a subset of all available
>      distributions or components at that location is desired.

I first tried
  deb file:///home/richard/dvdmount pool main contrib
Then
  deb file:///home/richard/dvdmount pool/main/
  deb file:///home/richard/dvdmount pool/contrib/

Both gave " ... does not have a Release file" messages.
The later also said:
> Updating from such a repository can't be done securely, and
> is therefore disabled by default.See apt-secure(8) manpage
> for repository creation and user configuration details.

I suspect I'm running up against two things:
1. Documentation (esp man pages) authors assume *ALL* readers have
   the same background they do. I don't. {I was on the other side
   ~50 years ago as an Engineering Co-op student writing the
   inspection manual for a new oscilloscope ;}
2. Changes in what apt identifies acceptable repositories.

I'm reading or re-reading:
   https://www.debian.org/doc/manuals/debian-handbook/index.en.html

   https://www.debian.org/doc/manuals/aptitude/index.en.html

   https://manpages.debian.org/stretch/apt/apt.8.en.html

   https://manpages.debian.org/jessie/apt/apt.8.en.html

   https://wiki.debian.org/SecureApt/TufDerivedImprovements

   https://manpages.debian.org/stretch/apt/apt-secure.8.en.html

   https://manpages.debian.org/stretch/apt/sources.list.5.en.html
with special focus on
   https://www.debian.org/doc/manuals/aptitude/index.en.html
   https://www.debian.org/doc/manuals/debian-handbook/apt.en.html
    "Chapter 6. Maintenance and Updates: The APT Tools"

I intend to experiment with modifying files in /etc/apt/apt.conf.d 
rather than modifying sources.list. This will require I dedicate a 
separate machine to the experiment. I will also use that machine to 
compare stretch to earlier releases.