Package: debian-installer User has a USB drive, loaded with $ mount /dev/sdg2 on /var/cache/apt/archives type ext4 /dev/sdg1 on /var/lib/apt/lists type ext4
He takes this drive, along with another drive, containing a Debian installation ISO, to a remote mountain (offline) computer, intending to install Debian on it. Alas, while running the ISO there is no way to tell it about the other stick where those the .debs are. Thus making an offline https://haydenjames.io/direct-install-debian-sid-rolling-release-using-mini-iso-w-screenshots/ not possible. See also https://wiki.debian.org/SourcesList#CD-ROM https://www.debian.org/releases/stretch/amd64/ch06s03.html.en#di-install-software "/etc/apt/sources.list. You can examine and edit this file to your liking **after** the installation is complete." Anyway the user would like to offline, have a way to say to the installer: This .... is the location of a lot of *.debs. and This ... is a Packages file I made from them. and This ... is a list of packages I want you to install from it. Sure, "just do that all later after you get Debain installed". But that is very wasteful.