Magic SysRq Key Sequences over Remote DRAC5 Connection
adam.nielsen at uq.edu.au
Sun Jun 6 21:07:58 CDT 2010
> Fixes and Enhancements:
> *SysRq magic key doesnt work on dell systems remotely
Funny, that doesn't show up on the page for me.
> Never mind the missing apostrophe... I've downloaded this release,
> installed it, and don't yet have remote Magic SysRq.
> I'm not quite sure what key sequence to type. In OpenSSH if I type ~B
> to send a break, I can't be pressing the ALT key at the same time.
> What exactly is Dell thinking will be at the remote end?
You don't need to hold Alt when working over the serial port.
Alt+PrintScreen on a PC keyboard sends the special SysRq keycode, which
is replaced by the 'break' on a serial console. So break+h over serial
should print the SysRq help message.
~B via OpenSSH doesn't work for me either. Looking at the source code
for the 'connect com2' program, it seems that it's a simple 'cat'
from stdin to the serial port, which wouldn't pass through any breaks (I
think these are sent via ioctls.) Perhaps this was fixed in the newest
firmware? I only have the source up to v1.48 to check.
A better alternative might be to write a program which is run directly
from the DRAC command line and sends a break + char, then dumps any
following output. Sadly Dell haven't released enough of the DRAC code
to make this possible.
which in turn runs
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