[CentOS-virt] Video resolution for CentOS guest

Tue Feb 24 04:53:40 UTC 2015
Digimer <lists at alteeve.ca>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 23/02/15 11:11 PM, Robert Nichols wrote:
> Would someone please point me to some reasonably current
> instructions for getting greater than 1024x768 video resolution for
> a CentOS 6 guest on a CentOS 6 KVM/qemu host?  When I search online
> I find stuff from 2009 and 2010 saying, "For details see ...," and
> linking to a URL that no longer exists, or pages that say, "You
> need to switch from VNC to Spice," and giving a long list of
> out-of-date instructions for doing so.  (With virt-manager it takes
> 2 clicks to do that.  Of course it doesn't help -- still maxes out
> at 1024x768.)
> 
> I've found that I can just append "vga=0x380" to the kernel
> command line and see Plymouth come up with the full graphical boot
> screen in the correct 1440x900 resolution, but as soon as gdm
> starts up, the display scrambles.  I find suggestions to generate
> an xorg.conf file, but no mention of what to put in it.  I can run
> "Xorg -configure", but the resulting file contains nothing about
> video modes, so it's not apparent what needs to be added.
> 
> I find it particularly annoying that a Windows 7 guest can set any 
> resolution I want up to 2560x1600, but a Linux guest can't go
> higher than 1024x768.

I played with this and found that, in fact, I had to switch the spice
/ qxl. With that change, I had no trouble pushing EL6 to much higher
resolutions.

- -- 
Digimer
Papers and Projects: https://alteeve.ca/w/
What if the cure for cancer is trapped in the mind of a person without
access to education?
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
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=SO1z
-----END PGP SIGNATURE-----