Now that we have a running Raspbian distribution in all the Raspberry Pi devices that we wish to use, we will now connect them to create a cluster. We would need a networking hub that has at least the same number of LAN ports as the size of your cluster should be. For the purposes of this chapter, we will use three Raspberry Pis, so we would need a hub that has at least three LAN ports.

If you have a Wi-Fi router, then it should already have some ports at the back, as shown in the following image:

We also need three networking cables, such as those with an Ethernet connector, where one port goes into the Raspberry Pi and the other goes into the networking hub. They will look like the ones shown in the following image:

Connect one end of the Ethernet cable to the Raspberry Pi and the other end to the router for all the devices. Once we complete this networking setup, we can move on to connecting the Raspberry Pi devices with software.