XP Guest for non-privileged OS X Users

sepp · Post by **sepp** » 17. Feb 2009, 14:37

Hi,

i'll try to figure out how to use VirtualBox in a Mac OS X computer lab for our students to give them a XP Guest system. What i did up to now was:

mkdir /VirtualBox with rwxrwxr-w belonging to me, beeing part of the admin group, students have 'other' rights

setenv VBOX_USER_HOME /VirtualBox

installed VirtualBox, created a XP VM with two hard disk, installed guest additions, made the hard disk immutable after installations, everything runs fine from my account.

now, when i log into OS X as a student and try to launch VirtualBox, i get:

"Could not lock the settings file '/VirtualBox/VirtualBox.xml'"

Of course, this happens because as a student i have only r-x permissions in /VirtualBox. On the other hand, i don't want to give students any chance to change anything in the virtual box settings (and the guest system as well).

Is there no way to do this?

Regards, sepp

ajmas · Post by **ajmas** » 18. Feb 2009, 21:31

How are the users logged in? Are they using a guest account, or one with their name? I would be interested in trying to reproduce the scenario if I have time, though I need to understand the operating conditions.

sepp · Post by **sepp** » 18. Feb 2009, 23:22

Hi ajmas,

users (students) are authenticated via ldap. That is, they log in (into OS X, the VirtualBox host) with their username and password. Therefore, they have restricted permissions on the system, and thus on the /VirtualBox directory i have created, too. They only have full access on their home directories, which are mounted from NFS.

[Edit: meanwhile, i think VirtualBox cannot handle this at the current state, because the VirtualBox GUI allows any user to change settings, like usb settings and so on. Clearly, the GUI and thus the user starting the GUI has to have write access to the VBOX_USER_HOME directory. However, for lab environments this is not really a good idea, because a user might change settings and quit, the next user in another course may find the environment mixed up. If this user isn't experienced, he/she may be unable to work. Thus, there should be something like a 'player', which just runs the VM - which is preconfigured by an admin...]

Regards,

sepp

ajmas · Post by **ajmas** » 19. Feb 2009, 00:00

Would it be possible to write a launcher that makes a copy of the master settings. The user would then use the copy that was created. When ever new user logs in the the copy would be overwritten with the default image. It may make things a bit slower, but it could be a compromise.

sepp · Post by **sepp** » 19. Feb 2009, 14:50

Ok, this could be a solution. However, i think resetting the settings is possible by VBoxManage calls, too? I think we need to write a VboxManage skript which is called on OS X login anyway, because we need to share a students home directory as well, and these are mounted via nfs. Thus, $HOME is valid when the student has logged in and not when i as an admin set up the vm, because i don't want to share my home...

I'll try this and will report here...

ajmas · Post by **ajmas** » 19. Feb 2009, 15:00

How about putting the stuff in /Users/Shared and then creating a symbolic link:

ln -s /Users/Shared/VirtualBox ~/Library/VirtualBox

sepp · Post by **sepp** » 19. Feb 2009, 16:02

that may work, but /users/shared is rwxrwxrwx, too, so what should be the benefit?