How do I use SysRq on Linux for the s390 (Z Platform) under z/VM?

When troubleshooting a Linux installation on the s390 + z/VM platform it's necessary to be able to collect the information for troubleshooting problems. Sysrq is one helpful tool that, like the x86 platform, is available on s390 + z/VM.

First, ensure kernel.sysrq is configured. To do this login into the system normally would and edit the /etc/sysctl.conf file, adding or modifying the sy...