Earlier, I was using GNOME and Firefox and the Mouse died. I had to kill the power, to get the box going again, because it doesn't have a reset switch; which is *not* an elegant way to get going. What key combination would get me going or to a shell? CentOS 5, fully updated, 32 bit. TIA!
Lanny Marcus wrote on Sat, 13 Dec 2008 13:03:42 -0500:
What key combination would get me going or to a shell?
Probably none. If it doesn't react to CTRL-ALT-DEL it's frozen to death.
Kai
On Sat, Dec 13, 2008 at 1:31 PM, Kai Schaetzl maillists@conactive.com wrote:
Lanny Marcus wrote on Sat, 13 Dec 2008 13:03:42 -0500:
What key combination would get me going or to a shell?
Probably none. If it doesn't react to CTRL-ALT-DEL it's frozen to death.
Kai: I tried that and I tried CTRL-F2, when it happened, but neither helped. Lanny
On Sat, 2008-12-13 at 14:06 -0500, Lanny Marcus wrote:
On Sat, Dec 13, 2008 at 1:31 PM, Kai Schaetzl maillists@conactive.com wrote:
Lanny Marcus wrote on Sat, 13 Dec 2008 13:03:42 -0500:
What key combination would get me going or to a shell?
Probably none. If it doesn't react to CTRL-ALT-DEL it's frozen to death.
Kai: I tried that and I tried CTRL-F2, when it happened, but neither helped. Lanny
Did you try switching to a virtual terminal, e.g. <CTL>-<ALT>-<F1>?
If the box is not totally frozen this should let you work at a command line. Then you might be able to restart the desktop with a telinit 3 and telinit 5 combination, look at log files to see if there are any messages, etc.
<snip sig stuff>
On Sat, Dec 13, 2008 at 3:50 PM, William L. Maltby CentOS4Bill@triad.rr.com wrote: <snip>
Did you try switching to a virtual terminal, e.g. <CTL>-<ALT>-<F1>?
Bill: I tried CTL-ALT-F2 and I tried CTL-ALT-DEL
If the box is not totally frozen
It was 100% frozen.
this should let you work at a command line. Then you might be able to restart the desktop with a telinit 3 and telinit 5 combination, look at log files to see if there are any messages, etc.
That hadn't happened for a long time. The next time it happens, I hope I can remember ALT-SysRq-b to try to reboot the box. Lanny
Lanny Marcus wrote on Sat, 13 Dec 2008 15:56:32 -0500:
I hope I can remember ALT-SysRq-b to try to reboot the box.
try it now.
Kai
On Sun, Dec 14, 2008 at 12:31 PM, Kai Schaetzl maillists@conactive.com wrote:
Lanny Marcus wrote on Sat, 13 Dec 2008 15:56:32 -0500:
I hope I can remember ALT-SysRq-b to try to reboot the box.
try it now.
Kai: Thank you! That was a great idea! It does not work on my box. Possibly it isn't in the Kernel? I also tried CTRL-ALT-DEL and that did not work either......
This morning, I had a problem with this box, while trying to use K3b. It couldn't find the CD-RW drive, when I was ready to write the data, although it saw the empty CD-R media in the drive and then crashed and the box rebooted. I am going to run Diagnostics, to see how the HD, RAM and Motherboard are. Lanny
Lanny Marcus wrote on Sun, 14 Dec 2008 13:44:25 -0500:
It does not work on my box.
That's why I suggested it. ;-)
Possibly it isn't in the Kernel?
It is, you have to
echo "1" > /proc/sys/kernel/sysrq
To enable it. Maybe you can put it in one of the sysconfig files, somebody here will know :-) It may still not work then depending on your keyboard.
I also tried CTRL-ALT-DEL and that did not work either......
That one should work if you are on the console. If you are in a window manager it depends if it gets trapped and passed by it or not.
Kai
Hi,
On Sun, Dec 14, 2008 at 16:40, Kai Schaetzl maillists@conactive.com wrote:
echo "1" > /proc/sys/kernel/sysrq
To enable it. Maybe you can put it in one of the sysconfig files, somebody here will know :-)
To do this on boot, add this line to /etc/sysctl.conf:
kernel.sysrq = 1
If you change on the file, you can make it live on the system by running "sysctl -p" (which will read /etc/sysctl.conf and do the equivalent of "echo ... >/proc/sys/.../..." for each of the settings in that file).
HTH, Filipe
On Sun, Dec 14, 2008 at 8:54 PM, Filipe Brandenburger filbranden@gmail.com wrote:
On Sun, Dec 14, 2008 at 16:40, Kai Schaetzl maillists@conactive.com wrote:
echo "1" > /proc/sys/kernel/sysrq
To enable it. Maybe you can put it in one of the sysconfig files, somebody here will know :-)
To do this on boot, add this line to /etc/sysctl.conf:
kernel.sysrq = 1
If you change on the file, you can make it live on the system by running "sysctl -p" (which will read /etc/sysctl.conf and do the equivalent of "echo ... >/proc/sys/.../..." for each of the settings in that file).
Thanks! I will make those changes, in the morning, when I'm more alert.
On Sun, Dec 14, 2008 at 4:40 PM, Kai Schaetzl maillists@conactive.com wrote:
Lanny Marcus wrote on Sun, 14 Dec 2008 13:44:25 -0500:
It does not work on my box.
That's why I suggested it. ;-)
That's why I test my backups, after I make them. I appreciate you suggesting that I test this, so that I knew it wouldn't work....
Possibly it isn't in the Kernel?
It is, you have to
echo "1" > /proc/sys/kernel/sysrq
To enable it. Maybe you can put it in one of the sysconfig files, somebody here will know :-) It may still not work then depending on your keyboard.
I also tried CTRL-ALT-DEL and that did not work either......
That one should work if you are on the console. If you are in a window manager it depends if it gets trapped and passed by it or not.
Thanks for the additional information!
Lanny,
Don't forget to enable the featuret... magic sysrq is disabled by default.
quoting from http://aplawrence.com/Words2005/2005_04_13.html:
"To use it, you need to have it enabled in your kernel (CONFIG_MAGIC_SYSRQ). It usually is; if you have a file called '/proc/sys/kernel/sysrq' you have this. To ENABLE the magic functions, you need a "1" in that file. If it has 0, Alt-SysRq just returns you to the previous console you were using."
-Gordon
On Sat, Dec 13, 2008 at 3:56 PM, Lanny Marcus lmmailinglists@gmail.com wrote:
On Sat, Dec 13, 2008 at 3:50 PM, William L. Maltby CentOS4Bill@triad.rr.com wrote:
<snip> > Did you try switching to a virtual terminal, e.g. <CTL>-<ALT>-<F1>?
Bill: I tried CTL-ALT-F2 and I tried CTL-ALT-DEL
If the box is not totally frozen
It was 100% frozen.
this should let you work at a command line. Then you might be able to restart the desktop with a telinit 3 and telinit 5 combination, look at log files to see if there are any messages, etc.
That hadn't happened for a long time. The next time it happens, I hope I can remember ALT-SysRq-b to try to reboot the box. Lanny _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
On Sun, Dec 14, 2008 at 1:47 PM, Gordon McLellan gordonthree@gmail.com wrote:
Don't forget to enable the featuret... magic sysrq is disabled by default.
quoting from http://aplawrence.com/Words2005/2005_04_13.html:
"To use it, you need to have it enabled in your kernel (CONFIG_MAGIC_SYSRQ). It usually is; if you have a file called '/proc/sys/kernel/sysrq' you have this. To ENABLE the magic functions, you need a "1" in that file. If it has 0, Alt-SysRq just returns you to the previous console you were using."
<snip> Thanks for that information. It happened again, awhile ago. I was using Gmail online, with Firefox, as I'm now doing, and the mouse just became inactive. I had to kill the power again, which is a horribly inelegant way to get out of that.
Lanny Marcus wrote: ...
Thanks for that information. It happened again, awhile ago. I was using Gmail online, with Firefox, as I'm now doing, and the mouse just became inactive. I had to kill the power again, which is a horribly inelegant way to get out of that.
Lanny,
Have you tried to ssh in from another system? Sometimes that works even with the keyboard/mouse totally frozen. If so you could "telinit 3 / telinit 5" or reboot with a bit more elegance.
Phil
Lanny,
You might want to look at this, for future reference:
http://en.wikipedia.org/wiki/Magic_SysRq_key
-Gordon
On Sat, Dec 13, 2008 at 1:03 PM, Lanny Marcus lmmailinglists@gmail.com wrote:
Earlier, I was using GNOME and Firefox and the Mouse died. I had to kill the power, to get the box going again, because it doesn't have a reset switch; which is *not* an elegant way to get going. What key combination would get me going or to a shell? CentOS 5, fully updated, 32 bit. TIA! _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
On Sat, Dec 13, 2008 at 1:50 PM, Gordon McLellan gordonthree@gmail.com wrote:
You might want to look at this, for future reference: http://en.wikipedia.org/wiki/Magic_SysRq_key
Gordon: Thank you! I bookmarked that URL and I will read it, slowly. Hoping not to need to kill the power to get out of that situation, the next time it happens. Lanny
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Filipe Brandenburger -
Gordon McLellan -
Kai Schaetzl -
Lanny Marcus -
Phil Schaffner -
William L. Maltby