Hi Guys,
In relation to this post
https://www.postgresql.org/message-id/flat/20171208104120.21687.74167%40wrigleys.postgresql.org,
this is pretty old stuff but for some people encountering this issue, try
deleting /etc/sysconfig/pgsql/postgresql-9.6. The issue as what I see
relies on the /etc/init.d/postgresql-9.6 script. Also only occurs when you
are actually retrying to re-install the package after it has been removed
or so.
Anyhow just an FYI :-)