To plan cluster nodes, you specify which ones will serve as
follower nodes. The one node in a cluster that is not a follower is the leader
node.
To
plan your cluster nodes:
Write down the host and port of each of the Dgraph processes for
each of the Oracle Endeca Servers that will host your data store.
You will need this information to identify which of your nodes
should serve as a leader node and to designate other nodes as follower nodes.
Provision a shared file system on which the data files for the
data store will be stored.
When you will install the Oracle Endeca Server and start the data
store on each of them, they should each point to the location of the data files
(for the same data store) on this file system and have access to these files.
(Read-only access is sufficient for follower nodes; write access is required
for the leader node.)
On the node you would like to designate as the leader node,
reserve the port 2181.
This port is used by the Cluster Coordinator service (unless you
configure it to use another port). You will also specify this port when
starting all nodes in your cluster.