Installing from CD

[Matthew Kuiken]

Tez wrote:
> Matthew Kuiken wrote:
>   
>> Just a little FYI, I'll assume you are using the CDs from Ship-it. 
>> The Ship-it CDs are desktop CDs.  They contain a lot of the packages
>> in compressed form in the squash-fs file system.  As such, IIUC, most
>> of those packages are not available as real packages to apt.  This
>> makes the desktop CD quite a bit less useful as an upgrade CD for an
>> existing installation.  If you really want an upgrade CD, the
>> alternate install CD would be *much* better.
>>
>> -Matt
>>
>>
>>     
> The desktop CD's do have a complete apt repository on them as well as a
> squash-fs file with the packages "installed" so you can use the "desktop
> cd" as an apt cdrom just as well as the alternative cd.
>   

This is how I understand it, so I could be wrong, but the packages that 
are "installed" for use in the live CD are not really there as normal 
packages.  Ubiquity copies the files out of the squashfs file in order 
to save space on the CD.  Since these files are accessed in a way that 
apt normally doesn't work, the packages in question are not available to 
apt.  The repository on the CD is for packages that are not used by the 
live session, but that are considered important enough to have along, 
such as the build-essential package and dependencies.  If I am correct, 
this means that most of the packages that need upgrading are probably 
not really there on the CD, as they are used by the live session.

I got the impression of this being the way the installer works because 
of the discussions on build-essential on the devel list, so I hope 
someone will correct me if this is not true.

-Matt