To sycnronise package installs from one debian (or other deb-packaged) system to another use:
to build a list of the package selection states on the 'source' system. This generates a two-column output which will mostly show "install" packages but you will most likely find other entries such as "deinstall" for packages that have be uninstalled but not purged:
source-server# dpkg --get-selections | tee dpkg-get-selections-ouput-from-source-server ... python install python-appindicator install python-apport install python-apt install python-apt-common install python-aptdaemon install python-aptdaemon.gtk3widgets install python-beautifulsoup install ...
On the target server the output of the above command could be used as-is to completely replicate the packages by following this sequence (note the first step is not necessary but it's a good idea to allow you to roll back a mistake!):
destination-server# dpkg --get-selections > backup-destination-server-get-selections destination-server# dpkg --clear-selections destination-server# cat dpkg-get-selections-ouput-from-source-server | pkg --set-selections destination-server# aptitude install
You can also use a tool called dselect (dselect install) but aptitude does the job.
Alternately if you just want to bring missing libraries over you can filter those out of the initial --get-selections output and then apply them to the destination server without clearing the selections:
destination-server# grep '^python' dpkg-get-selections-ouput-from-source-server | pkg --set-selections destination-server# aptitude install