Debian - Backup and restore instaled software

- This is just a quick post so i can remember how i did something -

So I have taken an old Ferrograph SDX display and put new firmware on it ready to integrate it into an XFD (more on this in a later post).

I have decided to drive the display using Perl as there is a requirement to get RSS and xml and parse it appropriately build the packets for the sign and send them to the serial port of the host PC. I chose Perl because it has all of that stuff ready to go and i can develop on my local pc (windows) and port it to Linux fairly easily.

Anyhoo, i had already built an IRC server using an old junked desktop machine for the teams to use as a communication tool, and i built that on top of Debian etch. I couldn't use the same machine for the XFD because it doesn't have a serial port. I got hold of another junked desktop machine with a serial port and installed ebian etch on there too, and soon realised i couldn't remember what software i had installed on the IRC box. I wanted to keep them in sync.

Backup list of installed software

to find out what software i had installed i used the dpkg command to list installed software:

$ dpkg --get-selections

I then redirected the output into a file to store the list of installed software.

$ dpkg --get-selections > ~/installed-software.log

on the other box i used sftp to fetch the file, and used that to select the software i wanted to install

All i had to do is type following two commands:

# dpkg --set-selections < installed-software.log

Now my list is imported i need to use dselect to install the package.

# dselect

Select 'i' at the menu for install the software, answering Y to the question about additional space.

Job done!