Spring data gives us strong support JPA. Spring boot simplified the configuration of Spring Data. The netgloo’s example shows how to access data with only a profile application.properties.
However, some people needs the datasource to be configurable throw external profile but not project inside profile. Ok, we can define a Datasource ourselves to replace the auto generated one by spring boot;

A little analysis of stack from a example from “Thinking in Java”

This is a basic storage sharing investigation in openstack. The cinder provides block storage to instances and the instances will use this virtual disk as glusterfs backend. Then the instances defined as gluster server will provide shared volumes to other clients.

Install openvswitch and configure sFlow

Introduction of configure virtual network and KVM based on libvirt.