My es5.5.2-cluster is always red

[lichehuo]

one of data-node is always red, its uptime upper 100.
my datanode:32c 128G.
my config as follow:
elasticsearch.yml

discovery.zen.ping.unicast.hosts: ["26.6.0.163:9310", "26.6.0.162:9310", "26.6.0.161:9310"]
discovery.zen.minimum_master_nodes: 2
gateway.recover_after_nodes: 5
http.max_content_length: 100mb
transport.tcp.compress: true
transport.tcp.port: 9300
discovery.zen.ping_timeout: 100s
discovery.zen.fd.ping_timeout: 100s
node.max_local_storage_nodes: 2
action.destructive_requires_name: true
indices.fielddata.cache.size: 5gb
indices.breaker.fielddata.limit: 40%
indices.breaker.request.limit: 60%
indices.breaker.total.limit: 70%
indices.requests.cache.expire: 5m
#use for head plugins
http.cors.enabled: true
http.cors.allow-origin: "*"

jvm:

-Xms30g
-Xmx30g

GC configuration

#-XX:+UseConcMarkSweepGC
#-XX:CMSInitiatingOccupancyFraction=75
#-XX:+UseCMSInitiatingOccupancyOnly
-XX:+UseG1GC
-XX:MaxGCPauseMillis=200

other configs are default.

[dadoonet (David Pilato)]

Please format your code using </> icon as explained in this guide. It will make your post more readable.

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I updated your question.

What are the logs of your master nodes? (Please format them).

Why did you change the default JVM GC settings?