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Introduction

You may have a Debian or Ubuntu server with a set of installed packages and you want to install exactly the same packages on a different server.
This HowTo will tell you how to easily do that.

Execution

To make a local copy of the package selection states:

# dpkg --get-selections "*" > myselections .txt  

Or use \* - "*" makes the myselections.txt file include package entries for "purge" too.

If you want to i.e. check only all the PHP packages installed, run:

# dpkg --get-selections "*php*"

Then you simply transfer this file to another computer, and install it there with:

# apt-get update
# dpkg --set-selections <myselections.txt
# apt-get -u dselect-upgrade

Cheers,
Marcin