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wabe wrote: |
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> Neil Bothwick <neil@××××××××××.uk> wrote: |
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> |
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>> On Thu, 27 Apr 2017 16:56:00 -0500, Dale wrote: |
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>> |
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>>> One thing about alt sysreq, once you get to a certain point, you |
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>>> have to go "all the way" with it. I've found that just the R and E |
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>>> generally gets things back to a point it is accessible and I don't |
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>>> have to go through it all. I think once you get to the I or S, |
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>>> it's all or nothing at that point. Even after the E, you may have |
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>>> to start/restart some init processes. FYI, I'm pretty sure the S |
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>>> is what syncs the file systems and the U unmounts everything. Of |
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>>> course, the B reboots. I can't recall what the others do exactly. |
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>> R resets the keyboard. E sends a SIGTERM to all processes except PID1, |
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>> which is why you need to restart services after pressing it. I sends a |
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>> SIGKILL similarly. As you say S syncs ass filesystems, U unmounts |
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>> filesystems and remounts them readonly and B reboots. |
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>> |
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>> Once you have got to E, you need to restart stuff. You may get away |
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>> with switching runlevels to bring up all your services, or you may |
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>> decide that once the system has got itself into a state that has you |
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>> reaching for SysRq, a reboot is in order. |
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> Most of the keys are documented here: |
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> |
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> https://wiki.ubuntuusers.de/Magic_SysRQ/ |
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> |
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> And even more in the kernel directory at Documentation/sysrq.txt. |
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> |
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> I will pin these synopsis onto the backside of my monitor. :-) |
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> |
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> -- |
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> Regards |
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> wabe |
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I have it on a small post-it-note stuck on the side of my monitor. I'm |
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not sure, may have been Neil or Alan, that posted it this way. |
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Reboot Even If System Utterly Broken. |
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That sort of stuck with me. Still, I look at the sticky note to be |
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sure. I found it on linuxhowtos.org which ironically, was translated |
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from a site in your language I think. lol |
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Anyway, it's handy to have around, just in case, and a little safety is |
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needed when it seems the Sun just went dark. I wish I had that when I |
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did the hal thing. Let's not go to far into that tho. |
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Dale |
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:-) :-) |
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