Mount VMDK on guest

Option 1: nbd

sudo modprobe nbd
sudo qemu-nbd -c /dev/nbd1 /path/to/vmdk
sudo mount # partitions

# to remove
sudo qemu-nbd -d /dev/nbd1
sudo modprobe -r nbd

Option 2: libguestfs-tools

Install libguestfs-tools, then:

virt-filesystms -a /path/to/vmdk
guestmount -a /path/to/vmdk -m /dev/whatever --rw /mnt/point

# to remove
guestunmount /mnt/point