# Discovery-ec2 plugin always tries to ping localhost / never finds the nodes that it should **URL:** \ **Category:** Elasticsearch\ **Created:** [December 11, 2018, 7:52pm UTC](https://discuss.elastic.co/t/discovery-ec2-plugin-always-tries-to-ping-localhost-never-finds-the-nodes-that-it-should/160433 "2018-12-11T19:52:39Z")\ **Posts on this page:** 1\ **Showing post:** 4
**Author:** ![a.sapien](https://avatars.discourse-cdn.com/v4/letter/a/f07891/32.png) [@a.sapien](https://discuss.elastic.co/u/a.sapien)\ **Post date:** [December 11, 2018, 7:55pm UTC](https://discuss.elastic.co/t/discovery-ec2-plugin-always-tries-to-ping-localhost-never-finds-the-nodes-that-it-should/160433/4 "2018-12-11T19:55:35Z")
cont... ```auto at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:37) [elasticsearch-6.5.2.jar:6.5.2] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_191] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_191] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_191] Caused by: io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: /127.0.0.1:9301 [2018-12-11T00:57:42,503][TRACE][o.e.d.z.UnicastZenPing] [ip-172-25-34-206] [1] opening connection to [{[::1]:9300}{2gfRXEeFQaui3c7kJ4lZkQ}{0:0:0:0:0:0:0:1}{[::1]:9300}] [2018-12-11T00:57:42,506][TRACE][o.e.d.z.UnicastZenPing] [ip-172-25-34-206] [1] failed to ping {127.0.0.1:9304}{fEHx1WWfSTqFdkOt7_Zrxw}{127.0.0.1}{127.0.0.1:9304} org.elasticsearch.transport.ConnectTransportException: [][127.0.0.1:9304] ``` So what am i missing with the EC2 discovery plugin that is causing the cluster to find "localhost" and repeatedly ping it? It looks like this exact issue was actually broached here, but this thread has no solution. > [@Elasticsearch "failed to send ping" error](https://discuss.elastic.co/t/elasticsearch-failed-to-send-ping-error/55125/8): > > Your posts are not formatted using \. That may explain the limit. I don't understand what is happening. You set network host: \_ec2\_ but got: [2016-07-11 09:57:33,797][INFO][transport] [dev-lambda-elastic-1] publish\_address {127.0.0.1:9300}, bound\_addresses {[::1]:9300}, {127.0.0.1:9300} It does not make sense. Are you sure that your configuration is applied? What happens if you set: network host: 192.168.0.1 It should fail. Here's the (slightly edited) config for this particular master node: ```auto bootstrap.memory_lock: true node.name: ${HOSTNAME} action.destructive_requires_name: true # default is unbounded indices.fielddata.cache.size: 1% cluster.name: BlahCluster discovery.zen.minimum_master_nodes: 2 # only data nodes should have ingest and http capabilities node.master: true node.data: false node.ingest: false http.enabled: false xpack.security.enabled: true xpack.monitoring.enabled: true path.data: /mnt/blah path.logs: /mnt/blah network.host: _ec2:privateIpv4_ plugin.mandatory: discovery-ec2 cloud.node.auto_attributes: true cluster.routing.allocation.awareness.attributes: aws_availability_zone discovery: zen.hosts_provider: ec2 ec2.groups: sg-BLAH ec2.host_type: private_ip ec2.tag.Cluster: SomeClusterTag ec2.availability_zones: us-west-1b,us-west-1c ec2.protocol: https ``` I have confirmed that `SomeClusterTag` is on every node I would expect to see in the cluster. I have confirmed that the security group `sg-BLAH` is on every node and allows port 9200 through 9400. I know that there is no problem with inter-node communications because when I add the hosts manually, the cluster has no problem assembling: ```auto discovery.zen.ping.unicast.hosts: [ "172.25.56.186", "172.25.48.249", "172.25.38.47", "172.25.51.137", "172.25.34.128"] ``` So what am i missing? --- _[View the full topic](https://discuss.elastic.co/t/discovery-ec2-plugin-always-tries-to-ping-localhost-never-finds-the-nodes-that-it-should/160433)._