I wanted to resize a VMDK, which
VBoxManage can't resize directly, so I used the Convert to VDI → Resize VDI → Convert to VMDK procedure described here.
For the last step, I could not find clear documentation of which
--variant corresponded to the "dynamically allocated" option I chose in the GUI when creating the original VMDK.
The documentation on
clonehd has this list of variants: Standard, Fixed, Split2G, Stream, ESX. It is not obvious from the names which of those is dynamically allocated, and there is no mention of which variants apply to which image formats.
The documentation on disk image files refers to the GUI options of "fixed-size" or "dynamically allocated", but uses the word "variant" to mean file format, and does not refer to the list above or any of its entries.
--variant corresponds to selecting "dynamically allocated" in the GUI?
This is with VirtualBox 5.0.32 r112930 on macOS Sierra 10.12.3 (16D32)