[syslinux] Dualhead issue

Gene Cumm gene.cumm at gmail.com
Wed Aug 16 14:34:45 PDT 2017

On Wed, Aug 16, 2017 at 4:33 PM, Ralf Mardorf via Syslinux
<syslinux at zytor.com> wrote:
> On Wed, 16 Aug 2017 12:46:46 -0700, H. Peter Anvin via Syslinux wrote:
>>Is that true for vesamenu only, or even for text mode syslinux?
> Hi,
> I'm using menu.c32 (text mode only), this is the complete config:

What about the simpler case without a menu?

DEFAULT Pussytoes

LABEL Pussytoes
    MENU LABEL Arch Linux Rt ^Pussytoes
    LINUX ../vmlinuz-linux-rt-pussytoes
    APPEND root=LABEL=archlinux ro
    INITRD ../initramfs-linux-rt-pussytoes.img

Do you see anything with just this?

On Tue, Aug 15, 2017 at 7:53 AM, Ralf Mardorf via Syslinux
<syslinux at zytor.com> wrote:
> Hi,
> my primary monitor is a LCD HDMI2 and the secondary monitor is a CRT
> VGA1. The CRT monitor is only turned on on demand, but always connected
> by VGA.
> The BIOS is shown on both monitors, but the syslinux menu only on the
> CRT, as long as the CRT is connected by VGA. Even if it's turned off,
> the syslinux menu isn't shown on the LCD connected by HDMI.

It's a BIOS or EFI CSM situation really.

Did you try powering off the PC, unplug the VGA monitor, then boot?
This would be another thing to test in addition to the above config.

> [root at archlinux ~]# pacman -Q syslinux
> syslinux 6.03-7

Thanks for the info.

> Is there a way to get the syslinux menu displayed on both monitors or at
> least only on the LCD monitor?

It's a BIOS situation really.

> FWIW xrandr shows HDMI1 and HDMI2, but there is only one HDMI output
> assigned to HDMI2.

Sometimes other outputs might be labeled strangely like a DVI as HDMI1.


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