Second monitor not appearing in vbox
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Second monitor not appearing in vbox
The second montior isn't appearing despite being set to exist. The "enable" button on the dropdown for virtual screen 2 is NOT grayed out, implying the button can be pressed, but pressing it does nothing. any idea on how to fix? I just want to be able to use virtualbox with 2 virtual monitor screens
e; heres an image of the button, idk why but pressing it just doesn't do anything theres no error message and my guest OS doesn't detect anything other than the 1 monitor
e; heres an image of the button, idk why but pressing it just doesn't do anything theres no error message and my guest OS doesn't detect anything other than the 1 monitor
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Re: Second monitor not appearing in vbox
It looks like you have not installed the Guest Additions. I don't know if that is necessary (I don't use multiple monitors in VMs), but it can't hurt.
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Re: Second monitor not appearing in vbox
I cannot install Guest Additions (keep getting an error during install), and I also was trying to do dual monitors, I believe after all my research that you NEED Guest Additions for this to work properly.
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Re: Second monitor not appearing in vbox
I believe I have it installed, but the process of installation was not clear to me. So I may have made a mistake.mpack wrote:It looks like you have not installed the Guest Additions. I don't know if that is necessary (I don't use multiple monitors in VMs), but it can't hurt.
Anyway to check if its installed properly?
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Re: Second monitor not appearing in vbox
Open the VM's vbox.log, search for the words "Guest Additions information report:". One of those lines will have the version of GAs installed if any.
Note that GAs in a Linux VM have prerequisites, same as for installing Virtualbox on a Linux host:
https://www.virtualbox.org/manual/ch02. ... nux-prereq
https://www.virtualbox.org/manual/ch04. ... ions-linux
Note that GAs in a Linux VM have prerequisites, same as for installing Virtualbox on a Linux host:
https://www.virtualbox.org/manual/ch02. ... nux-prereq
https://www.virtualbox.org/manual/ch04. ... ions-linux
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Re: Second monitor not appearing in vbox
00:00:28.892853 VMMDev: Guest Additions information report: Version 6.1.26 r145957 '6.1.26'scottgus1 wrote:Open the VM's vbox.log, search for the words "Guest Additions information report:". One of those lines will have the version of GAs installed if any.
Note that GAs in a Linux VM have prerequisites, same as for installing Virtualbox on a Linux host:
https://www.virtualbox.org/manual/ch02. ... nux-prereq
https://www.virtualbox.org/manual/ch04. ... ions-linux
00:00:28.892891 VMMDev: Guest Additions information report: Interface = 0x00010004 osType = 0x00053100 (Linux >= 2.6, 64-bit)
this was in the vbox.log. this should mean its installed correctly right?
I believe I have all prerequisites although I'm not super experienced with linux so i may have made a mistake
still it doesn't work
EDIT:
Something else I noticed, When I use fullscreen and click on view>Virtual Monitor 1 or 2> Use host screen 1 or 2
the screen will disappear and I have no way of getting it back even tho that the manager says the virtualmachine is still running, I dont know how to make it reappear so I'm always forced to shut it down or freeze it and then reopen it
the icon for the window will still be in the bottom but clicking on it does nothing and like i said at this point I can only stop and restart the system using the manager
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Re: Second monitor not appearing in vbox
The line shows a good GA install.
Please Start the VM from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the VM from within the VM's OS if possible. If not possible, close the Virtualbox window for the VM with the Power Off option set.
Right-click the VM in the main Virtualbox window's VM list, choose Show Log. Save the far left tab's log and the hardening log next to it, zip them, and post the zip file, using the forum's Upload Attachment tab.
Please Start the VM from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the VM from within the VM's OS if possible. If not possible, close the Virtualbox window for the VM with the Power Off option set.
Right-click the VM in the main Virtualbox window's VM list, choose Show Log. Save the far left tab's log and the hardening log next to it, zip them, and post the zip file, using the forum's Upload Attachment tab.
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Re: Second monitor not appearing in vbox
scottgus1 wrote:The line shows a good GA install.
Please Start the VM from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the VM from within the VM's OS if possible. If not possible, close the Virtualbox window for the VM with the Power Off option set.
Right-click the VM in the main Virtualbox window's VM list, choose Show Log. Save the far left tab's log and the hardening log next to it, zip them, and post the zip file, using the forum's Upload Attachment tab.
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Re: Second monitor not appearing in vbox
This is not good.
I would reduce VM RAM to 3072MB, enable 3D acceleration, and increase graphics RAM to 256MB. Then let's see where that takes us.
That's cutting it too fine on available RAM. Also, while you do have the GAs installed you have not enabled hardware acceleration.00:00:03.037191 Host RAM: 8108MB (7.9GB) total, 4472MB (4.3GB) available
...
00:00:03.240252 RamSize <integer> = 0x0000000100000000 (4 294 967 296, 4 096 MB, 4.0 GB)
I would reduce VM RAM to 3072MB, enable 3D acceleration, and increase graphics RAM to 256MB. Then let's see where that takes us.
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Re: Second monitor not appearing in vbox
How can you increase the Graphics RAM? My max is 128MB.mpack wrote: ...and increase graphics RAM to 256MB.
Nvermind, I found it:
Code: Select all
VBoxManage modifyvm "Name of VM" --vram 256
Last edited by Jetras on 15. Oct 2021, 17:24, edited 1 time in total.
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Re: Second monitor not appearing in vbox
I discovered just today that VirtualBox currently limits Linux guests to 128MB for some reason. Better stick with that. Do enable 3D acceleration however.Jetras wrote: How can you increase the Graphics RAM? My max is 128MB.
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Re: Second monitor not appearing in vbox
I found that you can get around the limitation with:mpack wrote: I discovered just today that VirtualBox currently limits Linux guests to 128MB for some reason. Better stick with that. Do enable 3D acceleration however.
Code: Select all
VBoxManage modifyvm "Name of VM" --vram 256
Shoot for the Moon, even if you miss you still made it among the stars!
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Re: Second monitor not appearing in vbox
The question was never "would it cause problems", it was "would it just waste RAM". And the answer appears to be: yes.
We got feedback from the devs on the VRAM limitation with Linux guests. It's not an error or an oversight. Linux uses a different mechanism than Windows to get accelerated graphics, so the extra simulated graphics RAM simply isn't needed. All you need is enough for basic buffering of (say) two or three frames. A 4K frame is around 33MB, so 128MB gives you 4 frames. Even two 4K monitors should be ok, though that does admittedly take you a lot closer to the margin.Jetras wrote:Code: Select all
VBoxManage modifyvm "Name of VM" --vram 256
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Re: Second monitor not appearing in vbox
3D acceleration causes my guest OS to mostly break, this might be a problem with the guest OS rather than vbox however but i'm not surempack wrote:I discovered just today that VirtualBox currently limits Linux guests to 128MB for some reason. Better stick with that. Do enable 3D acceleration however.Jetras wrote: How can you increase the Graphics RAM? My max is 128MB.
edit: i'll try some more stuff and come back afterward