Serial console not working

Adam Lackorzynski adam at
Mon Dec 21 23:16:48 CET 2015

On Mon Dec 21, 2015 at 23:03:59 +0100, Lluís Vilanova wrote:
> Hi there! I'm trying to find out why my setup is not booting on a real machine
> (some Dell PowerEdge R210 node; ned says it cannot find rom/l4re), but I'm
> unable to redirect output to the serial console.
> I'm able to use the serial console for both grub and linux, so it's not a
> hardware issue. An excerpt of my grub2 configuration:
>   serial --unit=1 --speed=115200 --word=8 --parity=no --stop=1
>   terminal_input serial
>   terminal_output serial
>   # ...
>   # for the linux entry
>   linux   /vmlinuz-3.16.0-4-amd64 root=UUID=7573ed62-a910-4b97-a577-dde47a16f87a ro console=ttyS1,115200n8 quiet
> Now, here's the entry I'm using for L4, which never gets me any output on the
> serial console:
>   menuentry 'Test' {
>     set root=(hd0,1)
>     multiboot /l4/bootstrap -serial
>     module /l4/fiasco -serial_esc -comspeed 115200 -comport 1
>     module /l4/sigma0
>     module /l4/moe rom/test.cfg
>     module /l4/l4re
>     module /l4/ned
>     module /l4/test.cfg
>     module /l4/bin/test
>   }

For GRUB2, the the config needs to look like this:

   menuentry 'Test' {
     set root=(hd0,1)
     multiboot /l4/bootstrap bootstrap -serial
     module /l4/fiasco fiasco -serial_esc -comspeed 115200 -comport 1
     module /l4/sigma0 sigma0
     module /l4/moe moe rom/test.cfg
     module /l4/l4re l4re
     module /l4/ned ned
     module /l4/test.cfg test.cfg
     module /l4/bin/test test

I.e. the first argument is the path where GRUB2 finds the file, the
second is the path that is presented to the OS. comspeed and comport are
the default so you can leave them out.

Adam                 adam at

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