Virtual Box screen resolution

lucmove · 09-29-2020, 09:19 PM

I've been struggling with this for hours. I have searched all over the web and found a lot of old information including menu options that don't even exist anymore. So I can't have screen resolution higher than 1024x768 in the Linux guest OS (Debian).

I have run the guest tools installer, but it seems it didn't work:

Code:

root@localvm ~# systemctl status vboxadd.service
Ï vboxadd.service
   Loaded: loaded (/opt/VBoxGuestAdditions-5.2.24/init/vboxadd; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Tue 2020-09-29 20:47:06 EDT; 1h 6min ago
  Process: 338 ExecStart=/opt/VBoxGuestAdditions-5.2.24/init/vboxadd start (code=exited, status=1/FAILURE)
 Main PID: 338 (code=exited, status=1/FAILURE)

Sep 29 20:47:02 localvm systemd[1]: Starting vboxadd.service...
Sep 29 20:47:03 localvm vboxadd[338]: VirtualBox Guest Additions: Starting.
Sep 29 20:47:06 localvm useradd[400]: failed adding user 'vboxadd', data deleted
Sep 29 20:47:06 localvm useradd[401]: failed adding user 'vboxadd', data deleted
Sep 29 20:47:06 localvm vboxadd[338]: modprobe vboxguest failed
Sep 29 20:47:06 localvm vboxadd[338]: The log file /var/log/vboxadd-setup.log may contain further information.
Sep 29 20:47:06 localvm systemd[1]: vboxadd.service: Main process exited, code=exited, status=1/FAILURE
Sep 29 20:47:06 localvm systemd[1]: Failed to start vboxadd.service.
Sep 29 20:47:06 localvm systemd[1]: vboxadd.service: Unit entered failed state.
Sep 29 20:47:06 localvm systemd[1]: vboxadd.service: Failed with result 'exit-code'.

The content of /var/log/vboxadd-setup.log:

Code:

modprobe vboxguest failed

Manual attempt to run 'modprobe vboxguest':

Code:

modprobe: FATAL: Module vboxguest not found in directory /lib/modules/4.9.0-6-amd64

What else can I do?

TIA

frankbell · 09-29-2020, 10:13 PM

No answers, but some questions:

In the VirtualBox settings for this particular VM, what are the "display" settings? (You may have to shut Debian down to see them fully).

What are the capabilities of your physical monitor?

What distro/version are you using (I see that your user agent reports Debian Stretch, but confirmation would be welcome)?

lucmove · 09-29-2020, 10:51 PM

The host and the guest are Debian 9.

My physical monitor is certainly better than 1024x768. The problem seems to be that installation of the guest tools is not working. VB can't load (build?) the corresponding kernel module.

ondoho · 09-30-2020, 01:37 AM

Quote:

Originally Posted by lucmove

The host and the guest are Debian 9.

frankbell surely meant the guest.

Quote:

My physical monitor is certainly better than 1024x768. The problem seems to be that installation of the guest tools is not working. VB can't load (build?) the corresponding kernel module.

Why don't you answer frankbell's questions first.

pan64 · 09-30-2020, 10:22 AM

I would say vboxguestaddition was not installed correctly (or somehow corrupted). From the other hand you can use a newer version, 5.2 is old.

sevendogsbsd · 09-30-2020, 10:27 AM

Are kernel headers required to build guest additions? Or kernel modules in general?

pan64 · 09-30-2020, 10:30 AM

Quote:

Originally Posted by sevendogsbsd

Are kernel headers required to build guest additions? Or kernel modules in general?

I think yes. https://linuxize.com/post/how-to-ins...ons-in-ubuntu/ (something like this)

sevendogsbsd · 09-30-2020, 10:33 AM

And OP said they installed guest additions but the posts are error messages of the service status and mod probe. I would like to see the messages (if any) of the actual installation of guest additions.

kilgoretrout · 09-30-2020, 12:03 PM

The error messages indicate that the vboxguest module was never built. You probably ran VBoxLinuxAdditions.run as an ordinary user instead of root or you don't have the kernel headers installed. If you run as an ordinary user the script will run but not create the vboxguest module. It's confusing because some things from guest additions will work but somethings, like screen resolution won't.

With your guest additions iso mounted run:

Code:

$ su
<enter root password>
# cd /media/cdrom0
# sh VBoxLinuxAdditons.run

If you don't have your kernel headers installed you'll get an error message at the end informing you of that fact and the module won't build. If that is the case, install the kernel headers with:

Code:

# apt install linux-headers-$(uname -r)

and rerun VBoxLinuxAdditions.run. The kernel module should build and on reboot your screen resolution problems will be fixed.
Note, in Debian, with every kernel update you will have to redo the above process because Debian doesn't automatically install the kernel headers when it installs a new kernel. Fortunately, Debian doesn't update the kernel that often but they recently did when updating from 10.5 to 10.6. Don't know if there was a kernel update for Debian 9, but if there was and your screen resolution broke after the update, this is why.