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Questions tagged [sysrq]

Key combinations made with alt, the sysrq key and another key are executed by the kernel whatever the state of the system; if it is frozen the classic command is to combine alt and the sysrq key with REISUB, which will safely close processes and reboot the system.

30 questions
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19 answers

Shut down computer from keyboard

Is there a keyboard shortcut available to shutdown the computer? I know I can use the Power button, but I would like to be able to it from the keyboard. If such a shortcut does not exist already, how do I set one?
umpirsky
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Alt + sysrq + REISUB doesn't reboot my laptop

On occasion, my laptop has become stuck so I've used the magic key combination of Alt + SysRq + REISUB to perform a safe reboot. However, it doesn't seem to work for me as when I press the B key to complete the magic key command it simply says,…
James White
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How can I enable the "magic sysrq key" on ubuntu desktop?

The magic SysRq key does not work on my Ubuntu 16.04 desktop. I imagine it's now disabled by default. My attempts to enable it did not work, and the only thing Google finds is a 2007 forum post from when it was apparently enabled by default. Can I…
Arlie Stephens
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How do I diagnose Hang on Shutdown?

Since one or two months ago, my laptop with ubuntu 12.10x64 hangs during shutdown. There's just a black screen, no harddisk activity, it justs sits there. I feel it happens near the end of a normal shutdown cycle, judging from time elapsed. Only…
Christoph
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1 answer

How to use Magic SysRq Key, if theres no SysRq key on my keyboard

https://en.wikipedia.org/wiki/Magic_SysRq_key According to this it's very important. What I can do? Can I rebind this key to something else?
user691979
7
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1 answer

ALT+SysRq+REISUB hangs at "resetting" (without actually resetting/restarting)

I'm trying Alt + SysRq + REISUB to see how it would be used to restart my system safely in case of emergency. However, I find that Alt + SysRq + REISUB hangs at "resetting" (without actually resetting/restarting) in Maverick. All other SysRq…
user12681
5
votes
1 answer

How can I troubleshoot why Ubuntu keeps crashing on my laptop?

I have a one year old Acer Aspire 4752G netbook running Kubuntu 12.04 LTS with all the latest distribution updates installed. It was previously running great until about a week ago when it suddenly started crashing repeatedly. Previously, on the…
Peter White
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How to give control over keyboard back to X server after Alt + SysRq + R trick

Situation: an application freezes the X server and no keyboard input works. So I use Alt+SysRq+R to take the keyboard out of raw mode (make the kernel take control of the keyboard away from the X server). I can then type Ctrl+Alt+F1, kill the bad…
Øystein Tråsdahl
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4
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1 answer

Ubuntu + PrtSc + AltGr = CRASH

On Ubuntu 15.10 and 15.04 on Lenovo t440p when I'm writing a code in Netbeans and accidently click button AltGr and PrtSc on same time it's crashed and reboot system. This not take action with fresh installed Ubuntu. This is backtrace from…
phreakbox
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How to get Alt+SysRq work on a Dell Latitude E6530?

I have a Dell Latitude E6530. The keyboard has a SysRq key (Fn+Home). However the magic keys (especially the famous REISUB) doesn't work. SysRq is enabled in /proc/sys/kernel/sysrq (I get 1 if I cat this file). It works from external USB…
Calimo
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Sysrq magic key functionality check

The first time my laptop froze, I used the Alt+SysRq REISUB and it worked. Next time it happened - it didn't work. I edited the 10-magic-sysrq.conf file's line kernel.sysrq = 176 (changed it to value 1). I want to be sure that next time my laptop…
Tzahi Leh
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3
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2 answers

Linux kernel on ubuntu 20.04 crash frequently

I am using Ubuntu 20.04 on Dell vostro 7500. But the whole system crash frequently. The symptom is the screen shows no response to keyboard event and mouse event(mouse cannot move or click), but the screen is still light and showing the graphic…
Simon
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Tracking down a system freeze

Hey there I am doing yet another edit with newly gathered information. So far there has been few responses here, so this will probably be the last one. I am running a ThinkPad P14s with Ubuntu 20.04. Some times the machine freezes completely and I…
Franz
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2 answers

How does Alt+SysRq work on a DellXPS13?

sometimes my laptop freezes and normally I use the "magic SysRQ" combination to reboot it. How does this work on my DellXPS13 ? The closest question I could find was this one: How to get Alt+SysRq work on a Dell Latitude E6530?. But no matter which…
Philipp
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1 answer

is it possible to create vmcore file?

here is my system: base os: ubuntu 16.04 ubuntu 18.04 on virtualbox mem 4G cpu 2core check kdump-config show it said "ready to kdump" then sysctl -w kernel.sysrq=1 to make crash echo c > /proc/sysrq-trigger after then screen is freezing also…
oops-again
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