Configure Local Network for a Raspberry Pi Cluster

Best practices for connecting and configuring a Raspberry Pi cluster to a local network.

Static IP

What is a static IP?

An IP address that doesn’t get changed or re-assigned by the network (home router in our case) even after a restart and/or shutdown.

Why does a RPi cluster require a static IP?

When you create a RPi cluster you usually also configure client(s) to communicate with it. Lets look at a few examples of such clients:

SSH by node name, using a local machine /etc/hosts file to assign names for every RPi cluster node (e.g. rpi-master, rpi-node)
Register one of the RPi nodes as a Kubernetes master node, setting its IP address on a local machine kube config file
Register these IP addresses within an Ansible hosts inventory

Note: These clients must work with static IP addresses to prevent a situation of which all clients must be aligned constantly on every newly assigned IP address for either of the RPi nodes.

In this section we’ll learn how to configure a static IP address on a TP-Link: Archer VR600 router.

Retrieve a device network address (from router dashboard)

Open the router Dashboard
Select Advanced tab and afterwards Network from the side menu
Under LAN settings -> Client List retrieve the MAC Address of a client named raspberrypi

Retrieve a device network address (from RPi server directly)

In case there isn’t a MAC Address column on the client list, we’ll retrive its value directly from the RPi server:

Find the IP address of the new RPi device from the router’s Client List as described on the previous section
Open a terminal shell session via SSH to the RPi server
```
1
ssh pi@<INSERT-IP-ADDRESS>
```
Important: You might require to supply the RPi server password in case the machine you are connecting from lacks the RPi server SSH private key in its SSH authentication agent (default password: raspberry).

Run ifconfig and acquire the network physical address (MAC address) by searching for eth0 and copying the HWaddr or ether value

ip addr show eth0 | grep "ether\b" | awk '{print $2}' | cut -d/ -f1

Reserve a static IP address

Open the router Dashboard
Select the Advanced tab
Go to Network -> LAN Settings -> Address Reservation
Click add and fill out the following:
- MAC Address: fill in the HWaddr / ether from the RPi node
- IP Address: select a higher range IP address e.g. 192.168.1.200 so it won’t get occupied
  
  Important: Make sure Enable this entry is selected.
Go to System Tools -> Reboot