grub-inst option to allow portable linux installations

[Mgr. Janusz Chmiel]

Dear specialists,
One very kind man has given Me a piece of advice several months ago. I have 
wanted to try to install Linux operating systém, Ubuntu of A external bootable 
USB harddrive. But when I AM using Vmwareplayer, when I remove SCSI0 virtual 
harddrive support from virtuál machine configuration file, when  I allow 
Vmwareplayer to access USB external harddrive I have used official Ubuntu 
installer to install Ubuntu to USB bootable external harddrive.
Everything have been worked like A charm. I could even boot The systém on my 
other standard non virtuál computer with UEFI firmware. Unfortunately, I Am 
occurring problém, that when I choose turn off The systém, harddisk do not 
correctly flush The cache so internal auto parking hardware routine is being 
forced to park harddrive heads and it is causing unpleasant sound. As A 
result,file systém integrity can be get to very bad state and after several 
uncorrect shutdowns, system fail to boot at all.
Do you think, if grub-inst do not allow to add special two command line options 
which allow users to install anr run Ubuntu and other Linux distros on A 
portable USB bootable media?
One man on The Orca mailing list have given Me those two commands but I have 
lost thids E-mail and developer can not remember The options.
When I have tried those two command line options, harddrive started to 
sshutdown correctly.
Or do you think, that it could be only my notion which can not be true?
Thank you very much for special two command line options.
With kindness regards.
Janusz Chmiel