serial console output goes away while booting

0

I added console=ttyS0,57600n8 to my kernel command line. I get the normal boot messages until this

[ 5.123106] EXT4-fs (sda1): mounted filesystem with ordered data mode. Opts: (null)
Begin: Running /scripts/local-bottom ... done.
done.
Begin: Running /scripts/init-bottom ... done.

Then no more output. I am trying to debug a kernel panic using kdump, but can't quite get kdump to work. I want the serial console to get kdump working.

[edit] I worked around the problem using a virtual machine.

Brian O'Dell

Posted 2012-08-17T17:19:56.877

Reputation: 103

1You should try removing the "quiet" and hte other option from the grub config too. I can't remember it's name now, sorry. If you post a picture about the grub config (at boot), I'll help you pinpoint the other option too. – Apache – 2012-08-17T17:32:17.670

do you want me to hit e and take a pic of the kernel arguments? – Brian O'Dell – 2012-08-17T18:22:25.553

Answers

1

You will almost certainly also need to update your inittab, or upstart configuration in addition to the kernel options.

init - /etc/inittab

T0:23:respawn:/sbin/getty -L ttyS0 57600 vt102

Upstart - /etc/init/ttyS0.conf

# ttyS0 - getty
#
# This service maintains a getty on ttyS0 from the point the system is
# started until it is shut down again.

start on stopped rc or RUNLEVEL=[2345]
stop on runlevel [!2345]

respawn
exec /sbin/getty -L ttyS0 57600 vt102

Zoredache

Posted 2012-08-17T17:19:56.877

Reputation: 18 453

Asked: 2012-08-17T17:19:56.877

Viewed: 1 334 times

Active: 2012-08-30T17:42:56.323