[BlueOnyx:25292] Re: 5210R-AlmaLinux-8.5 Display resolution out of range?

[Michael Stauber]

Hello Takehisa Obata,

> After completing the installation of
> BlueOnyx-5210R-AlmaLinux-8.5-20211112.iso, 
> it cannot be displayed on the connected monitor and the network settings
> cannot be made.
> #Display resolution out of range?
> I'm connecting a monitor that supports 1920x1080 60Hz.

I've never seen or heard anyone having that problem, as the screen you
get after BlueOnyx boots is a regular Linux text based console. The
resolution it uses (640x480 or 800x600) should be supported by any
monitor that has been manufactured in the last 30 years.

So before fiddling with this for too long it might be quicker to just
connect *any* other monitor you have and see if that makes a difference.

After all, once the network is configured, you can just use the GUI and
SSH to administer the server.

Other than that:

While the server boots you briefly see the Grub2 boot menu. Use the
cursor keys to pause the startup and select the first grub entry. Hit
"e" to edit the entry. Find the "kernel" line and append ...

vga=884

... at the end of it. That will configure the console to use another
resolution, namely 1600x1200. An abbreviated list is shown here:

http://pierre.baudu.in/other/grub.vga.modes.html

I *believe* 1980x1080 has the code 388, so you could try to use ...

vga=388

... as appended parameter.

HOWEVER: While that briefly switches to the chosen resolution, during
startup of the OS the defaults from /etc/defaults/grub or /etc/grub2/
kick in and you're back at square one.

A more permanent and dependable way to fix it might be this:

https://forums.centos.org/viewtopic.php?t=49321&start=10

That's for CentOS 7, but that also uses Grub2 and the principle is the
same on AlmaLinux 8. But I presume with the monitor you have connected
right now you might not get to a point where you can do that change.

But maybe someone else has an idea?

-- 
With best regards

Michael Stauber