Re: Squeeze dpkg --get-selections usable in any way in Wheezy?

[Lisi Reisz <lisi.reisz@gmail.com>]

On Tuesday 03 December 2013 22:51:11 Brad Alexander wrote:
> On Tue, Dec 3, 2013 at 5:39 PM, Neal Murphy 
<neal.p.murphy@alum.wpi.edu>wrote:
> > On Tuesday, December 03, 2013 05:26:37 PM Lisi Reisz wrote:
> > > I have had another failed upgrade.  Before I tried to upgrade,
> > > I ran dpkg --get-selections and saved the result in a file.
> > >
> > > I am obviously going to have to install Wheezy from scratch. 
> > > Is there any way I can make use of Squeeze's package list to
> > > give the owner of the box the same applications/packages as she
> > > had in Squeeze, mutatis mutandis?
> >
> > This topic was recently discussed, I think within the last 2-3
> > weeks. ... Ah,
> > 11/4: "Re: Installing same packages in a Squeeze installation in
> > a new Wheezy
> > installation". Excerpt from a thread summary I posted:
> >
> > ----
> > The theory is that --get-selections will list all installed pkgs
> > in a form that can be used by --set-selections to (re)install
> > them.
> >
> > So, on the existing system:
> >   # Mount a thumb drive; change 'sdg' as needed
> >   mount /dev/sdg1 /mnt
> >
> >   # Save the list of pkgs
> >   dpkg --get-selections > /mnt/current_installed_pkgs.txt
> >
> >   # Umount, then unplug the drive
> >   umount /mnt
> >
> > And on the new system, first netinstall a basic system. Then
> >   # Mount the thumb drive; change 'sdd' as needed
> >   mount /dev/sdd1 /mnt
> >
> >   # Set the list of pkgs to install
> >   dpkg --set-selections < /mnt/current_installed_pkgs.txt
> >
> >   # Unmount and remove the thumb drive
> >   umount /mnt
> >
> >   # Start the 'upgrade'
> >   apt-get dselect-upgrade
> > When done, the new system should have the same pkgs as the old
> > system. It won't be identical, but it'll be close.
>
> Neal beat me to the punch, Lisi.
>
> One point I would like to make is that it is probably not a bad
> idea to capture this from all of your machines as a starting point
> to have a pool of machine "types." For instance, being a believer
> in bastion hosts, I have a separate firewall, backup machine,
> fileserver, workstations, laptop, and containers (OpenVZ) for, for
> instance, mediawiki box, puppet master, etc. Each machine runs a
> script (installed by puppet) that runs at 4am that does an dpkg
> --get-selections and writes it to the filesytem. This is backed up
> daily. This way, if I am building a new box of a type, I have a
> base config from which to work.

Thanks to both of you.  I am most grateful.  

And that is a most useful additional suggestion, Brad. :-)

Lisi