virtualbox.org

I have six virtual machines that I use daily. On five of them, the shared folder works great. On the sixth and newest one, it doesn't.

This is a Lubuntu 18.04 VM running on an Ubuntu 18.04 host. My VBox version is Version 5.2.18 r124319 (Qt5.9.5)

* The Guest Additions version 5.2.18 installed without error.
* My user is in the vboxsf group
* I have rebooted multiple times

When I go to add the shared folder using the Devices/Shared Folders/Shared Folders Settings dialog, it accepts the inputs and emits no errors.

Yet, when I go to /media, the expected /sf_VM-shared is not there.

Please suggest troubleshooting steps. What log file should I look in? I see nothing in syslog. Or is there a terminal command for adding the folder, so that I can watch the output?

I'm baffled because this gave me no trouble on the previous VMs.

Edit - after posting this, I discovered more information.

This VM is a dual booter - it has a 18.04 install on one virtual drive and a 16.04 install on another virtual drive. (This was done to test the config before applying it to my physical server).

I've discovered that when I add the shared folder, it is getting added to the *16.04 install* which is not the one that the VM boots into by default! (It has the lowest numbered partition, which is why it gets chosen, I assume)

The other VMs are not multi-boot, which explains why I didn't have this issue.

So my question is now: On a multi-boot VM, how do I specify which install's "/" gets the shared folder?

Organic_Marble wrote:This VM is a dual booter ... This was done to test the config before applying it to my physical server

I don't think you're going to need functioning Shared Folders for your physical server, so why don't you skip that part of the test, and forget about it?

Dual-booting VMs are more rare than water on Mars, so I don't know how many people you'll find that they'll have some piece of advice.

Thanks.

Understand it's the corner-iest of corner cases, but trying stuff like this out before going to the hardware is the glory of VBox.

I'm in the process of cloning the VM and then I'll try swapping the order of the partitions so the one I use comes up first.

Organic_Marble wrote:trying stuff like this out before going to the hardware is the glory of VBox

Sure, but either I missed it, or it wasn't explained correctly. You're trying this scenario (dual-boot) before you commit your real computer through the same process. But, you won't be sharing a VirtualBox shared folder when you're in the physical world, that's what I'm trying to say.

Sure, it's a good question/exercise, but you won't actually use that scenario in RealLife™.

Yes, but this VM is now a simulation of my physical server, and I keep it up to date so that I can use it for troubleshooting/experimentation before applying changes to the physical server.

The shared folder aids in management.

My idea of swapping the partitions didn't work (although it was a fun exercise).

My only other idea is to renumber the partitions, but that is too much trouble, so I'm taking your advice and giving up.

Thanks again.