The SHUT_DOWN command in rascsi somehow takes effect faster than doing 'shutdown -h now' or 'reboot' on the shell. The rascsi OLED monitor script has an interrupt handler for graceful termination of the script, but it does not have time to fully execute when issuing a SHUT_DOWN command through rascsi.

This could very well be a bug with the interrupt handler I'm using in the python script, but raising this ticket for further investigation.