Installer & Kickstart options to disable hi-res video modes

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Got burned by this on RHEL6--the default to allow the kernel to use high-res text & graphics modes is nice on desktop/laptop hardware, but backfires big-time with data center equipment like ancient (7-year old) KVM switches & RAC/ILO-type server interfaces that can't grok (or simply doesn't have the network bandwidth to handle) the super-high-res modes that newer server hardware video chips support.  I know there is a kernel boot param that can be added to disable that, but the Installer itself should be thus limited by default _and_ should have a check-box + kickstart option to disable it from the git-go when installing systems.


you can put the installer in text mode?...

infact we rip out the framebuffer console stuff, remove the grub background image, get rid of the silly worm thing which covers the kernel boot details, and we remove 'quiet'


its all just options you feed to the kernel or set in grub, most of which you can do in anaconda either directly or in %post

If it can't read supported modes from the 'monitor' (which may be a virtual device, obviously), it should fall back to 1024x768. Is that not happening, or is even that too big?

Nothing in the datacentre should be running X11. Don't you guys use a kickstart to create a text console based install?

Yes, we do run a text-only operation--but 1) there are exceptions, such as first-time installs of a new major release before we have KS files built, and 2) thanks the "kernel mode setting" feature in RHEL6, even text mode can use very high-resolution video modes (as happened to me when booting an RHEL6 kernel on a Dell PowerEdge + DRAC vKVM...the text screen ended up split, top of the screen in the bottom of the window, bottom of the screen at the top, lots o' blank space in the middle.  Very hard to use :-( ).

You could potentially add "xmodule=vesa" to the boot parameters for your kernel and see if that helps you out any.

We kickstart all of our Dell boxes without X packages so I haven't seen Gnome in a little while.

If the box is a modern day shipping Dell server and you are seeing this (the RHEL6 vKVM issue), it wouldn't hurt to go to and file a bug report if there isn't one filed already.