Define Communication Paths

A Communication Path is a mechanism that allows the three nodes to communicate with each other and to transfer the data (for data replication purposes) between nodes. In a typical setup and especially in an on-premise environment, multiple communication paths are required to avoid a single point of failure. In this example, the network card in each node, or network routers switching between these nodes can be a point of failure.

In a cloud environment, however, having one communication path between nodes may be good enough as the underlying network layer is abstracted (we don’t have visibility of these layers).

The next step is to define communication paths between all pairs of nodes.

*Important Note: In a cluster consisting of three or more nodes, communication paths must be defined between all pairs of nodes. In a three-node cluster, this means that three communication paths must be defined (node-a ↔ node-b, node-a ↔ node-c, and node-b ↔ node-c).

1. Ensure both nodes are listed under the hosts file.
   1. Open elevated terminal
   2. run “cat /etc/hosts”
   3. If nodes are not listed, run “vim /etc/hosts” and add them accordingly with the IP addresses in the listed format below
      
2. Click “Create communication path”.

3. Select the following values. In most cases, these values should already be filled and selected.

4. The summary of what has been configured will be displayed. Select “Next”.

5. A communication path has now been defined.