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On Tue, Mar 31, 2015 at 1:57 AM, Fernando Rodriguez |
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<frodriguez.developer@×××××××.com> wrote: |
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> On Linux now there's the Magic SysRq Key feature for that. If enabled (I think |
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> it is by default, may be wrong) you can use ctrl-alt-sysrq plus one these keys |
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> even if your kernel panics or freezes in most cases (ctrl may only be needed |
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> from xorg): |
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> |
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> r - to get the keyboard back so you can switch to VT if xorg freezes |
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> e - to terminate all processes gracefully (SIGTERM) except pid 1 |
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> i - to terminate all processes forcefully (SIGKILL) except pid 1 |
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> s - to sync all filesystems |
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> u - to unmount them and remount readonly |
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> b - to reboot |
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You have to set "MAGIC_SYSRQ" to "y" for it to be enabled. |
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You can set the "capabilities" of sysrq either via |
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'MAGIC_SYSRQ_DEFAULT_ENABLE" or via sysctl. Debian uses the former (to |
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set it to 438) and Ubuntu and Fedora use the latter (to set it to 176 |
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and 16 respectively). "16" is systemd upstream's default whereby you |
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can only sync filesystems. It's the kind of value that can be the |
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source of a lot of arguing... |
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> Easy to remember as "Reboot Even If System Utterly Broken" |
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I remember it as the reverse of "busier". |
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