apt-clone lets you create "state" files of all installed packages for your Debian/Ubuntu systems that can be restored on freshly installed systems (or containers) or into a directory.
Use cases:
- clone server package selection and restore on fallback system
- backup system state to be able to restore in case of emergency
$ sudo apt-clone clone ~/myhost
will create an ~/myhost.apt-clone.tar.gz.
$ apt-clone info ~/myhost.apt-clone.tar.gz
Hostname: top
Arch: amd64
Distro: wily
Meta: ubuntu-desktop
Installed: 3308 pkgs (1469 automatic)
Date: Fri Nov 6 23:06:35 2015
The restore will override your existing /etc/apt/sources.list and will install/remove packages. So be careful!
$ sudo apt-clone restore ~/myhost.apt-clone.tar.gz
Note that you can give the option --destination /some/dir
and it will debootstrap the clone into this directory.