Running cat /etc/apt/apt.conf gives:APT::Default-Release stable;I thought doing that would disallow the command apt-get install wajig to work, if a newer version was available anywhere but Stable.How do I set up APT so that such a version would require me to specify the repository name in order to install it (e.g. apt-get --target-release testing wajig)?[update] I wasn't aware that my question wasn't so clear. I want this to be an archive-wide setting (i.e. it should apply to each package in the Stable archive), not to some specific package.
How to set default APT source
apt
Put this in your /etc/apt/preferences:Package: *Pin: release a=stablePin-Priority: 900Package: *Pin: release o=DebianPin-Priority: -10This is from man apt_preferences where P means Pin-Priority:500 < P <=990   causes a version to be installed unless there is a version available belonging to the target release or the installed version is more recentP < 0   prevents the version from being installedSee this Debian wiki page for something gentler than the manpage.