bugGNU GRUB - Bugs: bug #14893, Grub hangs on unattended boot if...


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bug #14893: Grub hangs on unattended boot if serial and console are configured

Submitted by:  None
Submitted on:  Mon 31 Oct 2005 09:04:59 PM UTC  
Category:  Booting Severity:  Major
Priority:  5 - Normal Item Group:  None
Status:  None Privacy:  Public
Assigned to:  None Originator Name:  Chris Gardiner
Originator Email:  -email is unavailable- Open/Closed:  Closed
Release:  0.93 Release:  None
Reproducibility:  Every Time Planned Release:  None

Sat 15 Dec 2007 09:00:31 PM UTC, comment #3: 

We've moved to GRUB 2 as a development platform. Please can you check if this bug still applies there, and if it does, reopen it?


Robert Millan <robertmh>
Project Administrator
Tue 29 Nov 2005 09:52:23 PM UTC, comment #2: 

Hi Everyone,
     I believe I have found the problem. Well, I was able to get mine working anyway. Here are the changes I needed to make.

serial --unit=0 --speed=9600 --word=8 --parity=no --stop=1
terminal --timeout=10 console serial
title CentOS (2.4.21-37.ELsmp) (console port output)
        root (hd0,0)
        kernel /vmlinuz-2.4.21-37.ELsmp ro root=/dev/md0 console=ttyS0,9600 console=tty0
        initrd /initrd-2.4.21-37.ELsmp.img
title CentOS (2.4.21-37.ELsmp) (serial port output)
        root (hd0,0)
        kernel /vmlinuz-2.4.21-37.ELsmp ro root=/dev/md0 console=tty0 console=ttyS0,9600
        initrd /initrd-2.4.21-37.ELsmp.img

There are only 2 things that really changed in the grub.conf file and 1 change in the BIOS settings.
1) I changed the order of the terminal line. I mis-understood the documentation and thought that the terminal would default to serial if it was first in the list. That apparently is incorrect. It will take the last in the list. This meant that the terminal line and kernal line were at odds with each other for an unattended boot.
I also broke the different boot methods out into their own entries, thus simplifing matters.
Most of this is all cosmetic or done for simplicity. What apparently was the real problem was a bios setting on the machine. There is a BIOS setting which says it will keep the terminal redirection agent active after kernel boot. Apparently on certain systems, Grub does not handle this being active very well. The instant I turn this setting off, the system boots up with out issue.

Well, I hope this helps.

Fri 04 Nov 2005 11:09:23 AM UTC, comment #1: 

i have the same problem

serial --unit=0 --speed=9600
terminal serial console
title Red Hat Enterprise Linux ES (2.6.9-5.EL)
        root (hd0,0)
        #kernel /boot/vmlinuz-2.6.9-5.EL ro root=LABEL=/ rhgb quiet
        kernel /boot/vmlinuz-2.6.9-5.EL ro root=LABEL=/ rhgb quiet console=ttyS0,9600 console=tty0
        initrd /boot/initrd-2.6.9-5.EL.img

ferry <ferry>
Mon 31 Oct 2005 09:04:59 PM UTC, original submission:  

Hi everyone,
     I'm hoping someine can help me out here. I believe this is a bug but can't be 100% sure I didn't just miss something. I have a CentOS (Basically redhat) system installed fresh off the CD's using Grub 0.93. Everything boots fine under normal circumstances. I recently added support for the system to run with a serial console and I'm running into issues. I have configured everything such that the console and serial terminal all work fine with one exception. When I attempt to boot the system unattended, the system hangs waiting for a key press to dertermine which console is the one to output to.
     By documentation, Grub is supposed to output to the device which has a key press during the time out interval or after the timeout, default to the first in the list. However, what I am seeing happening is that it times out and then hangs. Worst of all, if I wait long enough, no keypress on either the serial or the console will recover the system and I need to hard reboot. This is a SERIOUS problem. It basically means that I can not remotely reboot any server using a serial concertrator for console access without wathing the system come up.

    I am including a copy of my grub.conf file just in case I made some sort of simple mistake someone might see.

serial --unit=0 --speed=9600 --word=8 --parity=no --stop=1
terminal --dumb --timeout=2 serial console
#terminal --timeout=5 serial console
title CentOS-3 (2.4.21-32.ELsmp)
        root (hd0,0)
        kernel /vmlinuz-2.4.21-32.ELsmp ro root=/dev/md0 console=tty0 console=ttyS0,9600
        initrd /initrd-2.4.21-32.ELsmp.img
title CentOS-3-up (2.4.21-32.EL)
        root (hd0,0)
        kernel /vmlinuz-2.4.21-32.EL ro root=/dev/md0 console=tty0 console=ttyS0
        initrd /initrd-2.4.21-32.EL.img



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    Follow 3 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2007-12-15 robertmh Open/ClosedOpen => Closed
    2005-11-04 ferry Carbon-Copy- => Added ferry
    2005-10-31 None Carbon-Copy- => Added cgardiner --AT-- readytechs --DOT-- com

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