Re: apt-get/dselect - network *or* CDs

[Peter Hugosson-Miller <pehu@im.se>]

Rob Weir wrote:

> On Sun, Jul 06, 2003 at 10:03:07AM -0400, Kenneth Jacker wrote:
>
> > I've tried to find an answer to this by reading and searching the
> > net, but no luck.
> >
> > I created the "sources.list" file with network entries followed by CD
> > entries. Ideally, I'd like this setup to access one of the specified
> > network mirrors if I'm connected to the Internet. On the other hand,
> > if I'm not connected by either PPP or Ethernet, I'd like to use the
> > installation CDs.
> >
> > Is this possible?
> >
> > As a much less desirable "work around", I tried having two secondary
> > files -- one with the network entries and another with the CD ones --
> > one of which is symbolic linked to "sources.list". The problem with
> > that is when I use the network info, all the data from the seven CDs
> > "goes away" (requiring a rescan of all CDs next time I use *them*).
> >
> > Thanks for any ideas!
>
>
> There's no easy solution to this that I know of. If you have the
> diskspace, you could just copy the contents of this CDs to your hard
> disk, and then get packages from there, but that would require a few GB
> of space.
>
> Another solution might be to duplicate /var/lib/apt/ (and
> /etc/apt/sources.list) to /var/lib/apt.cdrom/ and /var/lib/apt.net/ and
> then symlink /var/lib/apt/ (and your sources.list) to which ever is
> appropriate at the time. I've never tried this, so test it carefully
> before you rely on it, and KEEP BACKUPS.

From the woody version of apt and later, if you put the cdrom entries 
_before_ the internet ones, then the CD's will be used in preference to 
the internet, as long as there is no newer version of the package on the 
net.

I think this might be the solution you are looking for. The only thing 
it _won't_ do, is if you wanted to say "use the CD's when I'm not 
connected to the internet, _even if_ there is a newer version of the 
package on the net". For that to work, I believe you would need to 
comment out the internet lines and do an "apt-get update" for the times 
when you were not connected, then uncomment them and "apt-get update" 
again next time you connected.

Any solution with multiple sources.list files would need to have the 
cdrom lines first in every file, otherwise you will need to rescan the 
CD's when you want those entries back in place. You can't manually add 
cdrom lines to sources list, for this you must use "apt-cdrom add".

--
Cheers,

  .~.
  /V\
 // \\
/(   )\
 ^`~´^
< hugge >