Need to create a Red Hat kickstart config to duplicate the installed packages off an existing system? Want to do this without having to create a giant file listing each RPM by hand?

Here’s a python script that will pull your installed packages list and prune it down by dependencies and yum groups, and give you a (hopefully) concise list of yum groups and RPMs that will work in a kickstart config file. The only complication is that you’ll need to ensure all your yum repositories are available at kickstart time, else you may run into some RPMs that are not available.

#!/usr/bin/env python
import yum

yb = yum.YumBase()
yb.doConfigSetup()
yb.doTsSetup()
yb.doRpmDBSetup()
    
# Grab Installed Package List (ipl)
ipl=set([pkg[0] for pkg in yb.rpmdb.pkglist])
grppkgs = set([])
# Grab Group List (gl)
gl=yb.doGroupLists()
# First index of gl is Installed Group List (igl)
igl=gl[0]

# Make sure we still are accounting for Core (sometimes packages get removed)
gotcore = False
for grp in igl:
    if grp.groupid == 'core': gotcore = True

if not gotcore:
    for grp in gl[1]:
        if grp.groupid == 'core':
           igl.append(grp)

# Find leaves of dependency tree
loners = ipl.copy()
for pkg in list(loners):
    deps= yb.findDeps(yb.returnInstalledPackagesByDep(pkg)).values()[0].keys()
    for dep in [d[0] for d in deps] :
        if dep in loners:
            loners.remove(pkg)
            break

# Print a kickstartable group list first
for grp in igl:
    for pkg in grp.mandatory_packages:
        if pkg in loners:
            loners.remove(pkg)
    for pkg in grp.default_packages:
        if pkg in loners:
            loners.remove(pkg)
    print '@'+grp.groupid

# Print rpms not pruned already
for pkg in loners:
   print pkg

Here’s a short python code to load up the local yum database, grab the list of yum groups, and print installed and available groups by short names (which can be used in kickstart scripts more easily than the output of yum grouplist.)

#!/usr/bin/env python
import yum
import sys

if __name__ == "__main__":
    yb = yum.YumBase()
    yb.doConfigSetup()
    yb.doTsSetup()
    yb.doRpmDBSetup()
    
    # Grab Group List (gl)
    gl=yb.doGroupLists()
    # First index of gl is Installed Group List (igl)
    igl=gl[0]
    # Second index of gl is Available Group List (agl)
    agl=gl[1]
    
    # Print a kickstartable group list
    print "Installed groups:\n"
    for grp in igl:
        print "@" + grp.groupid + ": '" + grp.name + "'"

    print "Available groups:\n"
    for grp in agl:
        print "@" + grp.groupid + ": '" + grp.name + "'"

Thanks to the for publishing a great starting point to yum python programming.