Migrating virtualbox storage from local disk to iSCSI

Turn off the virtual machine, preferably by logging in and do a clean shutdown or if not possible

VBoxManage controlvm <machine> poweroff

Add another disk

VBoxManage storageattach <machine> --storagectl "SATA Controller" –port 1 –type hdd –medium iscsi –server 192.168.100.13 –target "iqn.2004-06.net.strahlert.home:L1"

Boot the machine by FreeBSD 9.0 Install and start a Rescue Live shell

dd if=/dev/ada0 of=/dev/ada1 bs=1024000
poweroff

Detach the local disk and install cd and start the machine anew. It should now boot off the iSCSI disk