Enhancing the upgrade/install experience

[Bruno Wolff III]

On Tue, Nov 24, 2009 at 10:12:16 -0700,
  Jim Bevier <jim at jbsys.com> wrote:
> I need some help.....
> 
> During testing of different rawhide releases (alpha, beta, rc's,
> etc) I usually have an existing system and would like to install a
> "duplicate" of my old system.  This is also true if I upgrade from
> release to release.  I would like to get a list of existing packages
> (rpm -qa | sort > package_list) and somehow feed this into yum (or?)
> and have the packages installed if not already installed.  I would
> also need a list of packages that could not be installed. This way I
> could start with the live cd or install dvd, do a fresh install and
> then update to a duplicate of my old system.  So, is this
> functionality available?  Can it be?

You can use rpm -qa to get a list of what is installed now and save it
in a text file. There are options to get just the package name or you
can edit the file an do it there pretty easily. You can use those package
names on a yum install command later to get back the rough equivalent to
what you had before. You shouldn't expect to have the exact same set of
packages installed as new packages sometimes replace older packages or
dependencies change.