I have the following parameter on my CentOS 6.10 grub kernel parameter:

kernel /vmlinuz-2.6.32-754.10.1.el6.x86_64 ro … rhgb quiet vga=34A

(the vga=34A parm)

However when I reboot I have to reenter this parm every time.
BTW, the vga=34A parm gives me a 1600x1200x32 VESA resolution.

But, even though it's coded during reboot the message comes up:
Undefined Video Mode Number: 22
So I have to enter 34A manually.

Why does it accept this parm when I enter it manually and not automatically?
How can I set this as a permanant setting and where do I set it?

And better yet, when I move to CentOS 7 how do I or do I need to set this on grub2?
TIA
Gene

I see that you already have the option in the menu.lst. As far as I know the correct number for your mode is
vga=834

https://en.wikipedia.org/wiki/VESA_BIOS_Extensions

I don't know if you need to do the same but here are the steps.

CentOS 7 uses grub2. Edit the /boot/grub/grub.cfg and add your option to the GRUB_CMDLINE_LINUX_DEFAULT line. Run grub-mkconfig -o /boot/grub/grub.cfg to regenerate the grub.cfg file.

https://wiki.archlinux.org/index.php...arameters#GRUB

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I would think CentOS 7 will use kernels that implement KMS - the vga parameter will conflict IIRC.

Your probably correct but I have also read that CentOS7 still recognizes the vga kernel parameter.

You can manually add vga=ask to see all of the possible video modes.
You can use grubby to set the desired vga= parameter

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Moved: This thread is more suitable in <CentOS> and has been moved accordingly to help your thread/question get the exposure it deserves.

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Thank you all!
I've tested the solutions you gave and it is working just fine.
As far as the move to CentOS 7, that will have to wait because I've just become a great-grandfather and that is more important than any IT work.
TIA
Gene