The NCM DS host unexpectedly restarted, and are expecting to find stracktrace logs and core files in order to help explain why the DS restarted.
Alternatively, Support has asked for the stracktrace logs and core files and you're unable to find them.
NCM 10.1.X
In the event of a Device Server crash/ restart, you will be asked to collect core files, stacktrace and OS version info.
Screenshot example of a DS restart:
To collect the data, do the following :
$VOYENCE_HOME/diagnostics
$VOYENCE_HOME/diagnostics
cat /etc/redhat-release