Compressing a VirtualBox VDI file for a Windows guest running on a Linux Host

Recently, I had a situation where my the VDI files for my Windows 10 virtual machine expanded in size all of a sudden and I needed to reduce them. My downloading maps for use with Routebuddy may have been the cause so I moved the ISO installation files onto the underlying Linux Mint drives. With that space, I then set to uncovering how to compact the virtual disk file and the Sysinternals sdelete tool was recommend for clearing unused space. After downloading, I set it to work in a Powershell session running on the guest operating system from its directory using the following command:

./sdelete -z [drive letter designation; E: is an example]

From the command prompt, the following should do:

sdelete -z [drive letter designation; E: is an example]

Once, that had completed, I shut down the VM and executed a command like the following from a bash terminal session:

vboxmanage modifyhd [file location/file name].vdi --compact

Where there was space to release, VDI files were reduced in size to return more disk space. More could be done so I will look into the Windows 10 drives to see what else needs to be moved out of them.

Dropping back to a full screen terminal session from a desktop one in Linux

There are times when you might need to drop back to a full screen terminal session from a graphical desktop environment when running Linux. One example that I have encountered is the installation of Nvidia’s own graphics drivers on either Ubuntu or Linux Mint. Another happened to me on Arch Linux when a Cinnamon desktop environment update left me without the ability to open up a terminal window. Then, the full screen command allowed me to add in an alternative terminal emulator and Tech Drive-in’s list came in handy for this. there might have been something to sort on a FreeBSD installation that needed the same treatment. This latter pair happened to me on sessions running within VirtualBox and that has its own needs when it comes to dropping into a full screen command line session and I will come to that later.

When running Linux on a physical PC, the keyboard shortcuts that you are CTRL + ALT + F1 for entering a full screen terminal session and CTRL + ALT + F7 for returning to the graphical desktop again. When you are running a Linux guest in VirtualBox and the host operating system also is Linux, then the aforementioned shortcuts do not work within the virtual machine but instead affect the host. To get the guest operating system to drop into a full screen terminal session, the keyboard shortcut you need is [Host Key] + F1 and the default host key is the right hand CTRL key on your keyboard unless you have assigned to something else as I have. The exit the full screen terminal session and return to the graphical desktop again, the keyboard shortcut is [Host Key] + F7.

All of this works with GNOME and Cinnamon desktop environments running in X sessions and I cannot vouch for anything else unless alternatives like Wayland come my way. Hopefully, this useful functionality applies to those other set-ups too because there are times when a terminal session is needed to recover from a mishap, rare though those thankfully are and they need to be very rare if not non-existent for most users.

Moving a Windows 7 VM from VirtualBox to VMware Player

Seeing how well Windows 8 was running in an VMware Player virtual machine and that was without installing VMware Tools in the guest operating system, I was reminded about how sluggish my Windows 7 VirtualBox VM had become. Therefore, I decided to try a migration of the VM from VirtualBox to VMware. My hope was that it was as easy as exporting to an OVA file (File > Export Appliance… in VirtualBox) and importing that into VMware (File > Open a VM in Player). However, even selecting OVF compatibility was insufficient for achieving this and the size of the virtual disks meant that the export took a while to run as well. The solution was to create a new VM in VirtualBox from the OVA file and use the newly created VMDK files with VMware. That worked successfully and I now have a speedier more responsive Windows 7 VM for my pains.

Access to host directories needed reinstatement using a combination of the VMware Shared Folders feature and updating drive mappings in Windows 7 itself to use what appear to it like network drives in the Shared Folders directory on the \\vmware-host domain. For that to work, VMware Tools needed to be installed in the guest OS (go to Virtual Machine > Install VMware Tools to make available a virtual CD from which the installation can be done) as I discovered when trying the same thing with my Windows 8 VM, where I dare not instate VMware Tools due to their causing trouble when I last attempted it.

Moving virtual machine software brought about its side effects though. Software like Windows 7 detects that it’s on different hardware so reactivation can be needed. Windows 7 reactivation was a painless online affair but it wasn’t the same for Photoshop CS5. That meant that I needed help from Adobe’s technical support people top get past the number of PC’s for which the software already had been activated. In hindsight, deactivation should have been done prior to the move but that’s a lesson that I know well now. Technical support sorted my predicament politely and efficiently while reinforcing the aforementioned learning point. Moving virtual machine platform is very like moving from one PC to the next and it hadn’t clicked with me quite how real those virtual machines can be when it comes to software licencing.

Apart from that and figuring out how to do the it, the move went smoothly. An upgrade to the graphics driver on the host system and getting Windows 7 to recheck the capabilities of the virtual machine even gained me a fuller Aero experience than I had before then. Full screen operation is quite reasonable too (the CTRL + ALT + ENTER activates and deactivates it) and photo editing now feels less boxed in too.

Things that I like about VirtualBox OSE

Now that VirtualBox 2.0 is out with its 64 bit operating system support among other things, the version included in Ubuntu 8.04, OSE 1.56, is looking that bit older. Nevertheless, there remains a lot to like about the version that I have been using.

Screenshot: Windows XP running on VirtualBox OSE

Windows XP running on VirtualBox OSE

For one thing, its shared folders functionality doesn’t trip up Photoshop Elements like VMware does. VMware so hobbled Photoshop’s ability to save back to the Linux file system that it had me looking at the WINE route and I got to using GIMP for a while. VirtualBox brought me back into the Photoshop fold and I seem to like the results that I can get with Elements better than those from GIMP.

Another nicety is the way that guest OS desktops can be resized to fit in a maximised VM window. For this to work, you need VirtualBox Guest Additions in place in the virtual machine but it works very well when all is in place; my experience is with Windows XP. Full screen is on tap too once you use the Host+F combination; the right hand control key is usually the Host key by default. If there is any criticism at all, it might be that seamless application windows are not available in OSE 1.5.6.

Linux kernel changes can upset things but drivers don’t take too long to appear and you can always take matters into your own hands anyway. It’s a far cry from the blithe indifference of VMware and the need to resort to vmware-any-any patching to get things under way again.

All in all, VirtualBox OSE treats me very well. Guest operating systems may seem sluggish at times but it’s never enough to annoy or seriously impede usage. It’ll be interesting to see if a newer version of VirtualBox makes it into Ubuntu 8.10.