Cannot attach new vm via multiattach when another vm is running

[charlie-jacobsen]

Cf. bug report: https://www.virtualbox.org/ticket/11700. The suggested solution doesn't work if the vdi file is read only (on the file system).

After running the commands

NAME=test1

VBoxManage createvm --name "${NAME}" --ostype Ubuntu --register

VBoxManage modifyvm "${NAME}" --memory 1024

VBoxManage storagectl "${NAME}" --name "sata1" --add sata

VBoxManage storageattach "${NAME}" --storagectl "sata1" --port 0 --device 0 \

--type hdd --medium /path/to/my.vdi --mtype multiattach

to create a new vm (with an existing multiattach virtual disk), I start up the vm. While it's running, I create a new vm with similar commands, but I get the following error:

VBoxManage: error: Medium '/home/charlesj/vm/2100vm.vdi' is locked for reading by another task VBoxManage: error: Details: code VBOX_E_INVALID_OBJECT_STATE (0x80bb0007), component Medium, interface IMedium, callee nsISupports VBoxManage: error: Context: "COMSETTER(Type)(mediumType)" at line 678 of file VBoxManageStorageController.cpp VBoxManage: error: Failed to set the medium type

It looks like it's trying to set the medium type prematurely (in case it isn't multiattach).

Setting up a new vm with multiattach works when all attached vms are powered down / suspended, even when the vdi file is read only.

I've attached the log file for the first machine that successfully boots; the second machine does not produce a log file on failure.