Quite surprised no one reported this. I can't run Splunk anymore even fresh install on macOS Sierra.
Probably Splunk should alert users/engineers not to upgrade macOS before it's fixed.
Checking indexes...
homePath='/Users/philip/Projects/splunk_demo2/var/lib/splunk/audit/db' of index=_audit on unusable filesystem.
Validating databases (splunkd validatedb) failed with code '1'. If you cannot resolve the issue(s) above after consulting documentation, please file a case online at http://www.splunk.com/page/submit_issue
