1 Reply Latest reply on Oct 16, 2012 1:44 PM by houkouonchi

Anyway to force MSDOS partition layout

houkouonchi Oct 15, 2012 5:27 PM

When creating an appliance as CentOS the partition table/layout is MSDOS/MBR. When I make a fedora appliances it uses GPT/GUID. Unfortunately I have some things that don't have compatability with GPT/GUID for doing partition resizing/expanding. I was wondering if there was a way to force MBR/MSDOS instead of GPT/GUID in the appliances file?

I tried searching but didn't find my answer.

1. Re: Anyway to force MSDOS partition layout

houkouonchi Oct 16, 2012 1:44 PM (in response to houkouonchi)

I was able to force msdos by modifying:

/usr/lib/python/2.7/site-packages/appcreate/appliance.py.

I changed:

	# TODO: this most probably needs to be changed because we're not
	# resolving packages from package groups
	if 'grub2' in packages:
	self.grub = 'grub2'
	partition_layout = 'gpt'
	elif 'grub' in packages:
	self.grub = 'grub'

to:

	# TODO: this most probably needs to be changed because we're not
	# resolving packages from package groups
	if 'grub2' in packages:
	self.grub = 'grub2'
	partition_layout = 'msdos'
	elif 'grub' in packages:
	self.grub = 'grub'

I then ran into a problem of grub2 not wanting to install:

D, [2012-10-15T21:56:33.169421 #22952] DEBUG -- : Installing grub2 to /dev/loop2

D, [2012-10-15T21:56:34.190044 #22952] DEBUG -- : /usr/sbin/grub2-bios-setup: warning: your embedding area is unusually small. core.img won't fit in it..

D, [2012-10-15T21:56:34.198679 #22952] DEBUG -- : /usr/sbin/grub2-bios-setup: warning: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged..

D, [2012-10-15T21:56:34.199067 #22952] DEBUG -- : /usr/sbin/grub2-bios-setup: error: will not proceed with blocklists.

D, [2012-10-15T21:56:34.223045 #22952] DEBUG -- : Unable to create appliance : Unable to install grub2 bootloader

D, [2012-10-15T21:56:34.261776 #22952] DEBUG -- : Unmounting directory /appliances/build/appliances/x86_64/fedora/17/fedora17-cloudinit/1.0/fedora-plugin/tmp/imgcreate-xW0tTf/install_root/

I tried to force grub 1.x as I know it would not have a problem with little space between the partitions but I was able to edit

/usr/lib/python2.7/site-packages/appcreate/partitionedfs.py

and changed the partition offset to allow for more room from:

class PartitionedMount(Mount):

def __init__(self, disks, mountdir, partition_layout):

Mount.__init__(self, mountdir)

self.disks = {}

for name in disks.keys():

self.disks[name] = { 'disk': disks[name], # Disk object

'mapped': False, # True if kpartx mapping exists

'numpart': 0, # Number of allocate partitions

'partitions': [], # indexes to self.partitions

'extended': 0, # Size of extended partition

'offset': 0 } # Offset of next partition

to: