Elasticsearch ERROR not enough master nodes discovered during pinging - amazon-web-services

Question

# ======================== Elasticsearch Configuration =========================
#cluster.name: my-application
node.name: node-1
node.master: true
node.data: true
network.host: 172.31.24.193
discovery.zen.ping.unicast.hosts:["172.31.24.193","172.31.25.87","172.31.23.237"]
node-2 elasticsearch.yml configuration
# ======================== Elasticsearch Configuration =========================
#cluster.name: my-application
node.name: node-2
node.master: true
node.data: true
network.host: 172.31.25.87
discovery.zen.ping.unicast.hosts:["172.31.24.193","172.31.25.87","172.31.23.237"]
node-3 elasticsearch configuration
# ======================== Elasticsearch Configuration =========================
#cluster.name: my-application
node.name: node-3
node.master: true
node.data: true
network.host: 172.31.23.237
discovery.zen.ping.unicast.hosts:["172.31.24.193","172.31.25.87","172.31.23.237"]
Error description: I have installed an ec2-discovery plugin. I am passing AWS access key and secret key and endpoint in the elastic keystore.
I am using latest elastic search 6.2. I have started all the nodes on amazon ec2 instances. I have three instances of ec2.
I am getting the error on all the three nodes like this
[node-2] not enough master nodes discovered during pinging (found [[Candidate{node={node-2}{TpI8T4GBShK8CN7c2ruAXw}{DAsuqCnISsuiw6BGvqrysA}{172.31.25.87}{172.31.25.87:9300}, clusterStateVersion=-1}]], but needed [2]), pinging again

Answer 1

First,
to use ec2-discovery, you need to have this in your elasticsearch.yml:
discovery.zen.hosts_provider: ec2
and remove the discovery.zen.ping.unicast.hosts. please check https://www.elastic.co/guide/en/elasticsearch/plugins/current/discovery-ec2-usage.html
The idea of ec2-discovery is not to hardcode the nodes IPs in the config file, but rather auto 'discover' them.
Second,
the error you've provided shows that the nodes are not able to ping each other, make sure you set a rule in your security group to allow this. In the InBound tab, add a new rule:
Type: All TCP
Source: your security group id (sg-xxxxxx)