Graphic desktop poor resolution or black screen running on ESXi 6.0

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Environment

SUSE Linux Enterprise Server 12 SP2
SUSE Linux Enterprise Desktop 12 SP2
Xorg and Gnome/GDM installed for graphic desktop.

Situation

The login screen is displayed at a low 800x600 resolution which remains the same on the Gnome desktop after login. In the Gnome Tools under the display settings the only resolution available is 800x600.

An alternative symptom can be that a black screen with a mouse cursor is displayed rather than the graphic login screen.

Resolution

Make sure the system is updated. The graphics driver used for running under VMware is vmwgfx and is provided by the kernel-default package. In addition to the kernel package, make sure the open-vm-tools packages are up to date.

If the problem persists after updating then the next step is to disable KMS (Kernel Mode Setting) for the kernel.

1. Get to a text based terminal or ssh session on the system and edit (as the root user) /etc/default/grub.

2. Locate the line starting with "GRUB_CMDLINE_LINUX_DEFAULT=". At the end of that line, before the ending " add nomodeset. The line would look similar to this:

GRUB_CMDLINE_LINUX_DEFAULT=" resume=/dev/sda1 splash=silent quiet crashkernel=224M-:112M showopts nomodeset"

Save and exit the editor.

3. Run grub2-mkconfig to add the change to the grub configuration. As root:

grub2-mkconfig -o /boot/grub2/grub.cfg

4. Reboot for the kernel to run with the new parameter. After the system is booted confirm the parameter was included by running "cat /proc/cmdline" and verify that "nomodeset" shows up correctly.

With nomodeset in place the graphics should be displayed correctly and the display settings should allow a better selection for the resolution.

Cause

Some hardware/driver combinations do not work well with the kernel enabled mode setting. Turning KMS off for the kernel turns the responsibility over to Xorg and the graphics card driver (in this case vmwgfx). This problem does not seem to be happening (or at least not reported at this time) with later versions of ESXi (later than 6.0).

Disclaimer

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