One of the common problems that you hit when installing the GUI in a CentOS (Red Hat) Hyper-V guest is changing the default screen resolution – 1152×864. Most of the published solutions are for Ubuntu Hyper-V guests, and if you’ve come here, you are probably aware that they are not applicable for CentOS and Red Hat VMs.
In this short video, we demonstrate how to change the screen resolution in CentOS and Red Hat Hyper-V Virtual Machines using the grubby tool. The instructions are valid for both version 6 and version 7 of the OS. For your convenience, we provide the commands that we are using in the video:
# Use “grubby” to update all current and future kernels passing the video argument
# for the Microsoft Hyper-V Synthetic Video Frame Buffer driver
grubby –update-kernel=ALL –args=”video=hyperv_fb:1024×768”
# A reboot is required to apply the changes: