how to have two nodes on localhost server elasticsearch -

i'm working on localhost, , in order understand cluster , node is, want have 2 nodes on localhost.

just make clear: when lunch elasticsearch bin/elasticsear, i'm luching cluster, right?

if yes, node?

and how can have 2 nodes on cluster?

update

you may ask why need that?

it because, may know, each index in elasticsearch cluster has shads. default 5 shards 1 index, , default each index has 1 replica, each index default has 10 shards, 5 original data, , 5 replica. in elasticsearch, it impossible put replica's shards , original shards on same node. thus, in case, have 1 cluster running 5 original shards each index, don't have 5 replica's shads. that's why index status yellow (not green, not red), want green, need node in cluster put shards, have 1 elasticsearch server (localhost), that's why need node on localhost elasticsearch server

whenever start elasticsearch server master node gets default.in order run node, go terminal , start elastic-search server again. make sure that:

• discovery.zen.ping.multicast.enabled: true in elasticsearch.yml.

since elasticsearch distributed in nature, newly added instance automatically detected existing node(s).you can verify terminal.

suppose name of existing node node1 , newly added node node2.

• on terminal node1 running see message:

  [node1] added [node2]

• on terminal node2 has been started see message:

  [node2] detected_master [node1]

both nodes detected each other automatically. can run following query in sense check nodes running:

get /_cluster/state 

this list nodes