Hi,
On the Confluence page Install Bahmni on CentOS it is stated that CentOS 6.8 is deprecated and that
You should have to choose either CentOS 6.7 or CentOS 6.9 for Bahmni installation.
Are you sure that CentOS 6.8 is deprecated and CentOS 6.7 is still recommended?
A post in the CentOS forum states that all minor version releases are deprecated as soon as there is a new one available. So CentOS 6.7 should be deprecated as well in favour of CentOS 6.9.