Comment posted Reboot Safely a frozen (hanged up) Linux Server with Magic SysRQ Key combination by .
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You did not mention how to test if it is enabled
>Now to check if the magic sysrq is enabled
View CommentView Comment>on a server one should issue the command:
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Hello,
You can use:
sysctl -a |grep kernel.sysrq
You should get something like: kernel.sysrq = 1
Hope this helps
best,
View CommentView CommentGeorgi
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thanks.
One thing that is vague for me is that how someone can send magic sysrq from keyboard without sitting in front of server? Since all server activities are done remotely and normally we use putty to connect remotely. In case of a kernel crash, network is down and you can not ssh to a crashed server.
View CommentView CommentMozilla/5.0 (X11; U; Linux x86_64; en-us) AppleWebKit/531.2+ (KHTML, like Gecko) Version/5.0 Safari/531.2+ Debian/squeeze (2.30.6-1) Epiphany/2.30.6
Hi if you want a server to auto restart on crash, perhaps you would like to check my other article – (how to Automatically Restart GNU/Linux on kernel panic) – https://www.pc-freak.net/blog/how-to-automatically-reboot-restart-debian-gnu-lenny-linux-on-kernel-panic-some-general-cpu-overload-or-system-crash-2/
Also one other way is to use IPKVM / IKVM interface to restart the server if hanged remotely 🙂
Best!
View CommentView CommentGeorgi
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Hi
View CommentView CommentOne thing that is vague for me is that I remember upon a kernel panic, the num lock led is no longer working. Mean that the keyboard is also not responsive. So I wonder how that magic key work?