Problem with redirecting output to boot terminal
halfline at gmail.com
Tue Dec 14 12:07:26 PST 2010
(sorry for the slow reply)
On Sun, Nov 28, 2010 at 2:22 PM, Andrey Borzenkov <arvidjaar at gmail.com> wrote:
> It took me some time to understand why output from rc.sysinit was not visible.
> In initrd we start plymouthd and call "plymouth --show-splash". Now I
> do not have any splash to show (i.e. no "splash" on command line) but
> plymouthd still switches active console to boot terminal which in our
> case in tty7.
Even when "splash" is taken off the kernel command line, we still show
a splash called "details"
This splash basically just echos all data coming in and spews it back out.
It does do a little more if you have encrypted disks.
> Later rc.sysinit starts, checks whether splash is active and
> terminates plymouthd by calling "plymouth quit".
why do you quit plymouth that early?
One thing to keep in mind is, plymouth performs two primary functions:
1) boot splash
2) boot message logger
So even if you take "splash" off the kernel command line, it still
logs your boot.
Normally, you would run plymouth all the way until the end of boot up,
so that all boot messages get logged to /var/log/boot.log
> Only after next script starts anything appears on tty1.
> The question is - why would we switch to tty7 (or whatever is defined
> in configuration) when we know that no splash is going to be shown
> anyway? This splits boot output between several terminals and is
> really confusing.
Honestly, I think it's a better choice to run plymouth on tty1 and run
X on tty1. It makes the most sense looking at things from a "fresh"
perspective. It's only tty7 by historical accident, basically. I
recognize not everyone shares my view, though.
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