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On Sunday, March 29, 2015 12:23:00 PM lee wrote: |
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> Philip Webb <purslow@××××××××.net> writes: |
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> What's the last time you pressed Ctrl+Alt+Del and it actually worked? |
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> It's a legacy thing from times when freezes/crashes were common and when |
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> it did work and was useful. |
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> |
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> Nowadays, when you're pressing it, usually nothing happens anyway |
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> because the machine is down to where you have to press the reset button |
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> or to turn off the power (if you can't log in with ssh). When the |
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> machine still works, Ctrl+Alt+Del also works, which means that the |
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> default does nothing but create a security hole. |
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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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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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Easy to remember as "Reboot Even If System Utterly Broken" |
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There's a lot of other commands in the kernel docs sysrq.txt |
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> So how can we have this default changed? |
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Somebody posted that on this very thread. Replace the ctrlaltdel entry on |
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inittab with /bin/false. |
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-- |
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Fernando Rodriguez |
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