Why does the Splunk process die during AWS cloud formation? "helper process seems to have died (child killed by signal 15: Terminated"

I've got a CF template that does the Splunk configuration for a license/master server and the last step starts the splunk service. I've logged the output and see Splunk starting up fine. Once I log into the EC2 instance, I see Splunk has died. The splunkd.log shows this error: 08-03-2016 12:32:40.130 -0400 FATAL ProcessRunner - Unexpected EOF from process runner child! 08-03-2016 12:32:40.130 -0400 ERROR ProcessRunner - helper process seems to have died (child killed by signal 15: Terminated