Help, cant elect master

Elastic Stack Elasticsearch
1

Hi
I have a six node cluster trying to upgrade to 7 from 6.8. Can't elect a master. Each node is a docker container on seperate machines. The config files on master are set:

 cluster.name: "docker-cluster"
network.host: 0.0.0.0
node.name: "bex"
network.publish_host: 10.230.0.1
node.master: true
node.data: true

# minimum_master_nodes need to be explicitly set when bound on a public IP
# set to 1 to allow single node clusters
# Details: https://github.com/elastic/elasticsearch/pull/17288
# discovery.zen.minimum_master_nodes: 2
path.repo: ["/backups", "/nfsbackup"]

discovery.seed_hosts:
    - 10.230.0.4
    - 10.230.0.3
      ##discovery.zen.ping.unicast.hosts:
logger.org.elasticsearch.cluster.coordination: TRACE

cluster.initial_master_nodes:
    - 10.230.0.1
    - 10.230.0.3
    - 10.230.0.4

Nodes are called bex, el3, el4.

Log sample bex: https://pastebin.com/fz1u62rB

Log sample el3: https://pastebin.com/ASXScgHy

Any help enormously appreciated!

2

What is your discovery.zen.ping.unicast.hosts value in each node? can you share your elasticsearch.yml config file?

3

I read that had been depreciated in favour of seed nodes.

4

Your'e right.

5

I have same problem when I upgraded to 7.x

shutdown all cluster
update all elasticsearch.yml file and add following

cluster.initial_master_nodes: ## keep node1 as master at first try.

Start all elasticsearch.
once cluster up you can remove this line as now it will automatically elect master node.