I installed Hortonworks sandbox with HDP 2.4 on Windows 7 machine with 4 cores and 24GB memory. The sandbox is configured to have 4 processors and 12GB base memory. Is it pseudo distributed mode? Then, can each processor can have their names (like n1, n2, n3, and n4) and they can work as four-node cluster?
The sandbox is running in pseudo distributed mode, which means all of the processes for a cluster are running on a single machine. There is no concept of multiple nodes in your cluster; there is just a single node.
With enough resources on your machine, you could run 4 VMs and install HDP as a 4-node cluster. If you wanted to allocate a specific number of CPUs to your nodes, using VirtualBox or VMWare would be the way to accomplish that.