#607493 grub-pc: giving output to serial line *and* console isn't documented very well

Package:
grub-pc
Source:
grub2
Description:
GRand Unified Bootloader, version 2 (PC/BIOS version)
Submitter:
Martin Teufel
Date:
2010-12-19 02:06:05 UTC
Severity:
wishlist
#607493#5
Date:
2010-12-19 02:02:17 UTC
From:
To:
In difference to grub(-legacy), there is no option in grub2 to set a timeout for choosing whether to use the console or the serial line for the bootmenu.
In the grub2 manual, section 13.2.2 it is documented that you can do:
terminal_input [--append|--remove] [terminal1] [terminal2]
I needed some time to realize that that implies you can set
terminal_input serial console
terminal_output serial console
in grub.cfg, so that the menu goes to serial line and console concurrently.
After that, it was just a guess, that
GRUB_TERMINAL="serial console"
in /etc/default/grub would do it.

So my request is to make a clear mention to this in the grub manual section 13.2.2 and maybe include an example in /etc/default/grub like:
#GRUB_TERMINAL="console serial"  # for concurrent output of the bootmenu to console and serial line