[Libguestfs] [libguestfs/libguestfs] resize with ubuntu-20.04 (#63)

[Richard W.M. Jones]

On Mon, Feb 08, 2021 at 04:28:24AM -0800, Peter Willis wrote:
> Is there something I am missing to resize the disk in the ubuntu-20.04
> template?
> 
> # virt-builder ubuntu-20.04 --size 30G
> [   0.8] Downloading: http://builder.libguestfs.org/ubuntu-20.04.xz
> [   1.8] Planning how to build this image
> [   1.8] Uncompressing
> [  10.9] Resizing (using virt-resize) to expand the disk to 30.0G
> virt-resize: error: /dev/sda5: partition not found in the source disk image
> (this error came from ‘--expand’ option on the command line).  Try
> running this command: virt-filesystems --partitions --long -a
> /var/tmp/vb7ee275.img
> 
> If reporting bugs, run virt-resize with debugging enabled and include the
> complete output:
> 
>   virt-resize -v -x [...]
> 
> Or:
> 
> # virt-list-partitions -lh ubuntu-20.04.img
> /dev/sda1 vfat 512.0M
> /dev/sda2 unknown 1K
> /dev/sda5 ext4 5.5G
> # truncate -r ubuntu-20.04.img ubuntu-20.04-resized.img
> # truncate -s +5G ubuntu-20.04-resized.img
> # virt-resize --expand /dev/sda5 ubuntu-20.04.img ubuntu-20.04-resized.img
> [   0.0] Examining ubuntu-20.04.img
> virt-resize: error: /dev/sda5: partition not found in the source disk image
> (this error came from ‘--expand’ option on the command line).  Try
> running this command: virt-filesystems --partitions --long -a
> ubuntu-20.04.img
> 
> If reporting bugs, run virt-resize with debugging enabled and include the
> complete output:
> 
>   virt-resize -v -x [...]

The problem is that this image is incompatible with virt-resize:

$ virt-builder ubuntu-20.04
$ virt-filesystems -a ubuntu-20.04.img --all -l -h
Name       Type        VFS   Label  MBR  Size  Parent
/dev/sda1  filesystem  vfat  -      -    511M  -
/dev/sda5  filesystem  ext4  -      -    5.3G  -
/dev/sda1  partition   -     -      0b   512M  /dev/sda
/dev/sda2  partition   -     -      05   1.0K  /dev/sda
/dev/sda5  partition   -     -      83   5.5G  /dev/sda
/dev/sda   device      -     -      -    6.0G  -

Note the root filesystem is on a logical partition (/dev/sda5) which
virt-resize cannot handle:

https://libguestfs.org/virt-resize.1.html#logical-partitions

I wonder if there's a way to make Ubuntu templates that don't use
logical partitions?

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-builder quickly builds VMs from scratch
http://libguestfs.org/virt-builder.1.html