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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 keybord.

How can I have the Alt+SysRq+REISUB (in fact, Alt+Fn+Home+REISUB) reboot my system?

Calimo
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2 Answers2

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The Dell E6420 works as follows

  • Press/hold both Fn and Alt
  • Press/hold Home/Sysrq
  • Release Fn
  • Press key (tested with T)
Eric Carvalho
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Alessandro Suardi
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  • I realized that in step 3, you can release Fn OR bot Fn and Home/SysRq. Anyway this works on on the 6530 as well. – Calimo Sep 14 '13 at 10:18
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    how many hands do you need to perform this ? ;-) – solsTiCe Jun 21 '15 at 21:15
  • On a Dell Latitude 7300, I can confirm that only `Alt+Fn+R+b` (for reboot) seems to work: https://www.dell.com/community/Linux-Developer-Systems/how-to-generate-SysRq-key-combos-on-Dell-XPS-7390/td-p/7439878 – Mario Jun 28 '21 at 08:09
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The documentation (/usr/src/linux*/Documentation/sysrq.txt) says this:

On x86   - You press the key combo 'ALT-SysRq-<command key>'. Note - Some
           keyboards may not have a key labeled 'SysRq'. The 'SysRq' key is
           also known as the 'Print Screen' key. Also some keyboards cannot
           handle so many keys being pressed at the same time, so you might
           have better luck with "press Alt", "press SysRq", "release SysRq",
           "press <command key>", release everything.
elmicha
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    It's interesting to know it may be too much keys pressed at the same time, especially since I need to press Fn too. I tried releasing SysRq before pressing the command, to no avail. I also tested all the combinations with or without Fn, with Home (SysRq), End (PrntScrn) and others, but none worked. – Calimo Jul 27 '12 at 17:08
  • I tried plugging an external keybord, and that one works (I'll edit my question to mention this fact). – Calimo Jul 27 '12 at 17:09
  • Worked for me, the variant with releasing sysrq – majkinetor May 02 '13 at 11:37