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# NOTE: We need the system wide Python(2.6) because that's where
# the guestfs libs are installed (RHEL6.X)
# rpm package python-libguestfs is required for this to work
# yum install python-libguestfs
# Provide the disk image name as the only argument to this script
import guestfs
import sys, string
assert (len (sys.argv) == 2)
disk = sys.argv[1]
# For return values we want a dict object
g = guestfs.GuestFS (python_return_dict=True)
# Add our image
g.add_drive_opts (disk)
# Launch the guestfs back-end (same as run)
# Ask libguestfs to inspect for operating systems.
roots = g.inspect_os()
if len(roots) == 0:
raise (Error ("inspect_vm: no operating systems found"))
# We should get one device back, likely /dev/sda
devs = g.list_devices()
if len(devs) == 1:
dev = devs[0]
print "Found one device: %s" % dev
print "Found more than one dev, please specify which one you want to operate on.."
# We are expecting 2 partitions back from this device
# 1st part is boot partition
# 2nd part is pvs with root.fs and swap.vol in it
partitions = g.part_list(dev)
if len(partitions) == 2:
print "Found 2 partitions"
# double check that 2nd part is actually #2 and get it's start location
if partitions[1]['part_num'] == 2:
part_start = partitions[1]['part_start']
dev_part = dev + str(partitions[1]['part_num'])
print "cant find 2nd partition to modify.."
print "expected 2 partitions found %i instead" % len(partitions)
# Get block size
blk_size = g.blockdev_getss(dev)
print "Block size: %i" % blk_size
# Calculate start sector
start_sector = part_start / blk_size
print "Caclulated start sector: %i" % start_sector
# Delete 2nd partition on image
if g.part_del(dev, 2):
print "Parition delete failed.. Exiting"
print "Old partition removed"
# Flush device
print "Flushing buffers.."
# Recreate 2nd partition -1 means last sector
# NOTE: This command will issue a warning about the kernel failing to re-read the part table, this is ok and expected
# Actually it returns -1 even though it succeeds
g.part_add(dev, 'p', start_sector, -1)
except RuntimeError as msg:
print "Part add failed due to re-read of partition table, this is normal and expected.. Ignored.."
print "Partition created/expanded"
# Shutdown and restart guestfs to get our newly expanded partition table to be seen
print "Restarting guestfs (this takes a second)"
# Resize the PV
if g.pvresize(dev_part):
print "pvresize failed.. Exiting"
print "pv resized"
# Find and resize our volumes now
vols = g.lvs()
for vol in vols:
if string.find(string.split(vol, '/')[-1], "root.fs") >= 0:
print "root vol is: %s" % vol
root_vol = vol
if string.find(string.split(vol, '/')[-1], "swap.vol") >= 0:
print "swap vol is: %s" % vol
swap_vol = vol
if g.lvresize(swap_vol, 6144):
print "lvresize on swap failed.. Exiting"
print "lvresize on swap succeeded"
if g.lvresize_free(root_vol, 100):
print "lvresize on root failed.. Exiting"
print "lvresize on root succeeded"
if g.resize2fs(root_vol):
print "resize2fs on root vol failed.. Exiting"
print "resize2fs on root succeeded"
if g.e2fsck(root_vol, correct=True):
print "e2fsck on root vol failed.. Exiting"
print "e2fsck on root succeeded"
print "Resize completed, go ahead and boot the vm now"
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