I have followed the instructions to install a local repository for a segregated network. I apt-mirror to a local drive, rsynce to and external, then 'sneakernet' to the segregated networ. I can see the files when I go to http://inside-server/ubuntu. I've also updated two clients to point to the inside-server for the xenial files. One of these is the actual repo server.
The sources.list has:
deb http://inside-server/ubuntu xenial main restricted multiverse
I tried a few permutations of this line that I have found. However, I always get this error:
# apt update
Ign:1 http://inside-server/ubuntu xenial InRelease
Err:2 http://inside-server/ubuntu xenial Release
404 Not Found
Reading package lists... Done
E: The rpository 'http://inside-server/ubuntu xenial Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
#
I've spent three days googling and reading but the 'normal' directions all say my installation should just work. I looked at creating a key. That became involved and seemed out of the norm. My segregated network is trusted, so I looked at allowing an unauthenticated repository on the client. However, the man page for apt-secure points to apt.conf which is broken out in 16.04. I haven't yet found a clear example on what to change.
So, I'm punting. Anyone have any ideas?