Ubuntu kernel cleanup

kernel_cleanup.py

#!/usr/bin/env python
#
# This script will uninstall kernels that are not
# current running, or one of the two latest available.
#

import apt
import optparse
import os
import re
import sys
import subprocess as sub

if os.geteuid() != 0:
    print 'You must be root to run this script!'
    sys.exit(1)

# Setup command line arguments
parse = optparse.OptionParser()
parse.add_option('-d', '--dry-run', action='store_true', dest='dryrun')
(opts, args) = parse.parse_args()

# Get currently running kernel
p = sub.Popen(['uname', '-r'], stdout=sub.PIPE, stderr=sub.PIPE)
running_kernel, err = p.communicate()

# Generate apt cache
cache = apt.Cache()
installed = []
pending = False

# Find installed kernels
for pkg in cache:
    if re.match(r'linux-image-[0-9]\..*', pkg.name) and pkg.is_installed:
        installed.append(pkg.name)

# Mark kernels that are not running, or the two most recent
for kernel in installed[:-2]:
    version = re.match(r'linux-image-([0-9]\..*)', kernel)
    if (version.group(1) != running_kernel.strip()):
        print 'Marking inactive kernel {0} for deletion.'.format(kernel)
        pending = True
        if not opts.dryrun:
            cache[kernel].mark_delete()

# Uninstall old kernels
if pending and not opts.dryrun:
    print 'Removing old kernels:'
    cache.commit(fetch_progress=None, install_progress=None)
elif pending and opts.dryrun:
    print 'Dry run, exiting.'
else:
    print 'No kernels found for removal, exiting.'