Linux force reboot/shutdown

Posted on March 2, 2009 by smshaker

Forcing reboot

Linux is not Windows XP and if reboot fail you usually still connect by SSH and do something. This commands will show you how to remotely hard reboot machine. Hard reboot mean that shutdown scripts will not run and machine reboot immediately without syncing hard disk drives, shutdown applications etc, it’s more like hitting the reset button.

echo 1 > /proc/sys/kernel/sysrq

echo b > /proc/sysrq-trigger

This commands enable sysrq and after this calls fast reboot. If you want to force shutdown machine try this.

Force shutdown

echo 1 > /proc/sys/kernel/sysrq

echo o > /proc/sysrq-trigger

Pasted from <http://blog.air4web.com/linux-force-reboot.html>

This came handy, when I had a server that had some IO error and it can no longer read from disk, only few cached binaries into memory kept it running (kernel, SSHD, bash), I could still access the machine via SSH but can no longer do anything, forcing the reboot as mentioned above was my only resort, and it worked like charm…

Filed under: Software fun, Work Work Work | Tagged: , , , |

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8 Responses

  1. RaZoR, on June 10, 2009 at 1:55 am said:

    Great tutorial, really help me. Thx.

    Reply
  2. Ray, on July 22, 2009 at 6:50 am said:

    Thanks. That helped when I accidentally deleted my root RAID unit.

    For other people looking for this information via Google, I’ll say I:
    removed root RAID drive and unmounted root file system using
    3ware 3dm2 raid controller card. 🙂

    Reply
  3. Ben, on May 14, 2011 at 1:49 am said:

    I use this every day! omg I wish I didn’t but I totally do. thanks!!!!!

    Reply
    • smshaker, on May 15, 2011 at 6:14 pm said:

      Well, is “Thanks” here a good thing or a bad thing (just being sarcastic) 😀 …
      Either way, I’m glad it helped 🙂

      Reply
  4. Linux force reboot/shutdown « Sameh M. Shaker’s Weblog « iPAS's Technical Notes, on January 10, 2012 at 9:44 am said:

    […] Linux force reboot/shutdown « Sameh M. Shaker’s Weblog. Share this:FacebookTwitterLike this:LikeBe the first to like this post. Categories: Information […]

    Reply
  5. Michael, on March 24, 2013 at 1:58 pm said:

    Brilliant! I was doing something really stupid with my RAID controller management tools and put the server in a bad state. I was about to submit a ticket to the colo facility and drop down a couple of C-notes in the process, but you saved the day.

    Reply

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