virtualbox.org

We are using Oracle Box in our school under windows 7 64bit clients.

It's been working well on around 60 hosts for students doing coding.

We make the virtual windows installation immutable and have the clients physical H:\ drive mapped in to the virtual windows.

Occasionally we get reports from the students that when they start the virutal windows installaton they do not get an H:\


In explorer they can type \\vboxsrv then click on the \\Vboxsrv\h_drive icon and they have access fine.


They can also use the command:
net use H: \\Vboxsvr\h_drive

which works.


I am struggling to see why on random PC's the H:\ drive does not automatically appear when they are all setup identical...

Since a) this is occasionally and b) the network share is found later on, I would suspect that it's the Windows networking not working. I've had a similar issue when I was setting up a 200-computer network, with actual computers (way before virtualization). Have the affected student log-out and log-in again.

Thanks for your reply.

The host is unaffected and the problem persists after logging off and on and even after multiple reboots.

I suspect a bug with the guest additions as it looks like if they are re-installed the issue fixes itself.

I will update with more later....after a bit more testing.

We've just had one other affected PC "fixed" by re-installing the guest additions.

However, as the client or VM has an immutable disk then the issue must be being fixed by whatever re-installing the guest additions does to the host.

Is there anyway to track what that might be?

As a quicker fix for us might be a file replacement or registry tweak.

Regards

Reinstalling the GAs in a guest does nothing to the host. More likely, reinstalling the GAs ended by restarting the guest, and the restart was the real fix.

Hi,

Thanks for your response but I'm afraid that does nt sit with our observations.

We have given the guest OS and host OS multiple reboots and it does not fix the issue, however reinstalling the GA's does, even though the hard disk of the guest OS is set as immutable.

From reading here w w w virtuatopia com/index.php/Understanding_and_Installing_VirtualBox_Guest_Additions#VirtualBox_Guest_Additions_Features
it does suggest the GA's do more than edit JUST the guest OS settings...

The GAs are simply applications/drivers running inside the guest, some of which talk to a API provided by VBox in the host. Reinstalling the GAs without a version change should do nothing except reset the VBox-guest API, which is also what would happen if you simply restart the guest. There may be a chance element involved. Otherwise, I'm at a loss to explain your observations.

When we next have an incident of this happening do you think there is anything we could try prior to fixing by re-installing the GA's ?