Elasticsearch cluster: node not able to connect to cluster

Hi,

I have created a 2-node cluster of Elastic search. But on the data node, I get the below error:

[2016-09-30 11:36:16,156][INFO ][discovery.zen ] [VM-04] failed to se
nd join request to master [{VM-05}{uA5qlZYTT4ybmuZgLT7OZQ}{10.97.252.12}{10.97.2
52.12:9300}], reason [RemoteTransportException[[VM-05][10.97.252.12:9300][intern
al:discovery/zen/join]]; nested: ConnectTransportException[[VM-04][10.97.252.11:
9300] connect_timeout[30s]]; nested: NotSerializableExceptionWrapper[connect_exc
eption: Connection timed out: no further information: /10.97.252.11:9300]; ]

Settings in elasticsearch.yml:

1: Data node
cluster.name: elasticsearch
node.name: VM-04
node.master: false
network.host: "10.97.252.11"
discovery.zen.ping.unicast.hosts: ["10.97.252.11:9300","10.97.252.12:9300", "10.97.252.13:9300"]

2: Master node
cluster.name: elasticsearch
node.name: VM-05
network.host: "10.97.252.12"
discovery.zen.ping.unicast.hosts: ["10.97.252.11:9300","10.97.252.12:9300", "10.97.252.13:9300

What am I missing?