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You learn something new everyday! Using scale mode and VNC with VirtualBox to get a decent display resolution for a VM!

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I was trying to get the display resolution for a Linux Virtual Machine to a reasonable value - the host has an old PCI video card and can only do 1024 by 768 so the VM has been restricted to less than that even when using VNC (ie Remote Desktop for non-Windows machines).

I was experimenting with the various modes that Virtual Box allows when I realised that after setting the Virtual Machine to Scaled Mode I was able to choose a resolution that was higher than the resoltuion of the host. It did look pretty odd on the Host but when using VNC it is fine!

I can now control the Virtual Machine and see much more in the window!


24 May: After updating the network router I found my Linux Virtual machine would now lock up. So I created a new one using Fedora Core 20. However I was not able to get anything greater then 1012 by 664 (the host is stuck at 1024 x 768!).

So after some digging I found the following in the Virtual Box help.

VBoxManage setextradata global GUI/MaxGuestResolution any

Run this from a terminal window to set the maximum allowable resulation to be greater then the hosts.

 The options are (copied from the help for VirtualBox):

VBoxManage setextradata global GUI/MaxGuestResolution any
will remove all limits on guest resolutions.
VBoxManage setextradata global GUI/MaxGuestResolution >width,height<
manually specifies a maximum resolution.
VBoxManage setextradata global GUI/MaxGuestResolution auto
restores the default settings. Note that these settings apply globally to all guest systems, not just to a single machine.

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