I tried, and failed, today to send a “Magic Sysrq” to a linux box to which I was connected by a console server. I’m using Mac OS X. Is this even possible? If so, how?
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I tried, and failed, today to send a “Magic Sysrq” to a linux box to which I was connected by a console server. I’m using Mac OS X. Is this even possible? If so, how?
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AFAIK, the “Magic SysRQ” gets its magic from it being picked up by very low-level code in the keyboard handler in the kernel, which would preclude it working via any sort of network connection.
Unless you mean that the “console server” is a KVM box of some sort, in which case it should work, unless it filters out certain combinations (for its own use?).
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Yeah, that’s what I was afraid of. Thanks.
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Good question! So by “console server” you mean you’ve got a serial console? If so, sending a BREAK ought to do it, provided magic sysrq is compiled in and enabled (cat /proc/sys/kernel/sysrq — should be 1).
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Sadly that did not work on this machine, but it turned out that it was so badly horked that it needed to be unplugged physically.
I’m going to find a machine that’s hooked up to that thing which can be futzed with and find a recipe that works.
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