Elastic search 7.0 cluster master node handover problem

cluster.name: qiniu-ELK
node.name: node-2-master
path.data: /var/lib/elasticsearch
path.logs: /var/log/elasticsearch
network.host: 110.242.49.24
http.port: 9200
discovery.seed_hosts: ["110.242.49.23","110.242.49.24"]
cluster.initial_master_nodes: ["110.242.49.23", "110.242.49.24"]
gateway.recover_after_nodes: 1
indices.query.bool.max_clause_count: 8192
search.max_buckets: 100000
discovery.zen.minimum_master_nodes: 1

main node configuration