[syslinux] no display what can I try.

[Gene Cumm]

On Tue, Dec 19, 2017 at 3:47 PM, Jeff Sadowski via Syslinux
<syslinux at zytor.com> wrote:
> I have an odd issue.
> I have one machine that does not display to the monitor when it goes
> to a linux boot loader.
> It has the issue with grub and pxelinux.
>
> I see the bios but between bios and graphics driver I see a blank screen.
>
> Any recommendations on how to fix it?
>
> More to it. It is a newer nvidia card, That I need to drive a 4K
> monitor at 60Hz . If I replace it with an old nvidia card I can see it
> fine but it doesn't get me 4K at 60Hz.
>
> In grub I tried setting the resolution to 1024x768 using
>
> GRUB_GFXMODE=1024x768
>
> and ran "upgrade-grub"
>
> But I still ended with a blank screen.
>
> I really want pxelinux more than grub in hopes that some way I could
> boot clonezilla via pxe boot.
> Which I have working for the rest of my machines.
>
> I have a second video card that has the same symptoms in that machine
> but not in another.
> So something about motherboard+video card+(maybe monitor) that causes
> the issue. If someone has some suggestions of something to pass to
> pxelinux via it's config that I could try out I'd much appreciate it.
>
> my pxelinux config looks like so
>
> default vesamenu.c32
> #menu resolution 800 600
> #prompt 1
> #timeout 30
>
> display boot.msg
>
> label local
>   menu label Boot from ^local drive
>   menu default
>   timeout 20
>   kernel chain.c32
>   append hd0
> label memtest86
>   menu label ^Memory test
>   kernel memtest
>   append -
> label Clonezilla-live Stable 2017-02-20 x64
>   menu label Clonezilla Live 2017-02-20 x64 (Stable)
>   kernel cz170220.x64/live/vmlinuz
>   append initrd=cz170220.x64/live/initrd.img boot=live union=overlay
> username=user hostname=clonezilla config quiet components noswap
> edd=on nomodeset nodmraid noeject locales=en_US.UTF-8
> keyboard-layouts=NONE ocs_live_run="ocs-live-general"
> ocs_live_extra_param="" ocs_live_batch=no vga=788
> toram=filesystem.squashfs ip=dhcp net.ifnames=0  splash
> i915.blacklist=yes radeonhd.blacklist=yes nouveau.blacklist=yes
> vmwgfx.enable_fbdev=1 ocs_prerun="dhclient && mount -t nfs
> loki:/ifs/it/sysadmin/clonezilla /home/partimag"
> fetch=tftp://10.0.100.78/cz170220.x64/live/filesystem.squashfs

For starters, the keyword "quiet" silences all messages from Syslinux
and the Linux kernel.  Most initrds also adhere to this.
"nouveau.blacklist" controls an nVidia driver.

Consider also firmware upgrades/downgrades to the motherboard and
graphics card.  On occasion, you work around a bug in the current
firmware with a mildly older one.

Beyond that, it's distro-specific or hardware-specific.

Also, I hope the initrd/rootfs uses DHCP itself as some DHCP clients,
including some PXE clients, send a DHCPRELEASE, invalidating the lease
to allow other clients to use it.

-- 
-Gene