I find it convenient to install the oracle 11gr2 rdbms on Oracle Enterprise Linux 5, running as a virtual host using VirtualBox VM (That way i dont have to go through the pains of installing it on Ubuntu Linux, which is unsupported). I use this database on a daily basis for testing different oracle functionality.
I use the following virtualbox command line commands to start and stop the virtual machine. It is much faster that booting up the operating system and then starting oracle.
To stop the virtual machine(I have named the VM OEL7) , in its current state (With the oracle rdbms running)
$ VBoxManage controlvm OEL7 savestate
To start it
$VBoxManage startvm OEL7
It takes about 10 seconds to start it.
To make a clone of the Virtual Machine to a entirely new location. First shutdown the virtual machine and then
$VBoxManage clonevm OEL7 –options keepallmacs –name OEL7E –basefolder “/media/ExternalDrive/vimage2″
The –basefolder can be specified to be a new location on disk to create the new image.