To join a new Linux node to an existing cluster:
On a node that exists in a cluster, note the following:
The hostname or IP address of the host
The cluster join token, which is obtained by executing: sudo cspctl cluster token
On the node that is joining the cluster, execute the following:
sudo cspctl cluster join -s <hostname> -t <token>
Note that the hostname and token values were obtained from the existing node in the cluster you are joining (step 1). The process takes 5-15 minutes to complete.