# Unicast cluster - nodes fail to connect v2.1.0 **URL:** \ **Category:** Elasticsearch\ **Created:** [December 23, 2015, 11:55pm UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897 "2015-12-23T23:55:45Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![zetian](https://avatars.discourse-cdn.com/v4/letter/z/f14d63/32.png) [@zetian](https://discuss.elastic.co/u/zetian)\ **Post date:** [December 23, 2015, 11:55pm UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897/1 "2015-12-23T23:55:45Z")
I am trying to set up a new v2.1 unicast cluster but each node fails to see any of the other named nodes in the cluster. There is no data, no current load on these windows 2012 servers. I have scaled it back to two nodes to test. What am I missing? This is an example 'elasticsearch.yml' : ``` cluster.name: CPS-PD node.name: "chdp-es01" network.host: 10.1.2.191 discovery.zen.ping.multicast.enabled: false discovery.zen.ping.unicast.hosts: ["10.1.2.191", "10.1.2.192"]` ``` I set discovery to TRACE and I don't even see a ping response from the other node and it fails to connect every 30s. There is a strange looking string "{B7JRjusgQ\_6bP1YTg1nBAA}" associated with the current node : ``` [2015-12-23 17:12:06,583][TRACE][discovery.zen.ping.unicast] [chdp-es01] [1] sending to {chdp-es01}{B7JRjusgQ_6bP1YTg1nBAA}{10.1.2.191}{10.1.2.191:9300} [2015-12-23 17:12:06,692][TRACE][discovery.zen.ping.unicast] [chdp-es01] [1] received response from {chdp-es01}{B7JRjusgQ_6bP1YTg1nBAA}{10.1.2.191}{10.1.2.191:9300}: [ping_response{node [{chdp-es01}{B7JRjusgQ_6bP1YTg1nBAA}{10.1.2.191}{10.1.2.191:9300}], id[1], master [null], hasJoinedOnce [false], cluster_name[CPS-PD]}, ping_response{node [{chdp-es01}{B7JRjusgQ_6bP1YTg1nBAA}{10.1.2.191}{10.1.2.191:9300}], id[2], master [null], hasJoinedOnce [false], cluster_name[CPS-PD]}] [2015-12-23 17:12:06,708][TRACE][discovery.zen.ping.unicast] [chdp-es01] [1] connecting (light) to {#zen_unicast_2#}{10.1.2.192}{10.1.2.192:9300} [2015-12-23 17:12:11,251][TRACE][discovery.zen] [chdp-es01] full ping responses: {none} [2015-12-23 17:12:11,251][TRACE][discovery.zen.ping.unicast] [chdp-es01] [1] disconnecting from {#zen_unicast_2#}{10.1.2.192}{10.1.2.192:9300} [2015-12-23 17:12:11,251][DEBUG][discovery.zen] [chdp-es01] filtered ping responses: (filter_client[true], filter_data[false]) {none} [2015-12-23 17:12:11,251][DEBUG][discovery.zen] [chdp-es01] elected as master, waiting for incoming joins ([0] needed) [2015-12-23 17:12:11,267][INFO][cluster.service] [chdp-es01] new_master {chdp-es01}{B7JRjusgQ_6bP1YTg1nBAA}{10.1.2.191}{10.1.2.191:9300}, reason: zen-disco-join(elected_as_master, [0] joins received) [2015-12-23 17:12:11,267][TRACE][discovery.zen] [chdp-es01] stopping join accumulation ([election closed]) [2015-12-23 17:12:11,267][TRACE][discovery.zen] [chdp-es01] cluster joins counter set to [1] (elected as master) [2015-12-23 17:12:11,329][INFO][http] [chdp-es01] publish_address {10.1.2.191:9200}, bound_addresses {10.1.2.191:9200} [2015-12-23 17:12:11,329][INFO][node] [chdp-es01] started [2015-12-23 17:12:11,345][INFO][gateway] [chdp-es01] recovered [0] indices into cluster_state [2015-12-23 17:12:27,753][TRACE][discovery.zen.ping.unicast] [chdp-es01] [1] failed to connect to {#zen_unicast_2#}{10.1.2.192}{10.1.2.192:9300} ConnectTransportException[[][10.1.2.192:9300] connect_timeout[30s]]; nested: ConnectException[Connection timed out: no further information: /10.1.2.192:9300]; ``` ---
**Author:** ![warkolm](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/warkolm/32/39224_2.png) [@warkolm](https://discuss.elastic.co/u/warkolm)\ **Post date:** [December 23, 2015, 11:58pm UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897/2 "2015-12-23T23:58:11Z")
Is it a firewall issue? ---
**Author:** ![zetian](https://avatars.discourse-cdn.com/v4/letter/z/f14d63/32.png) [@zetian](https://discuss.elastic.co/u/zetian)\ **Post date:** [December 24, 2015, 12:01am UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897/3 "2015-12-24T00:01:58Z")
I do not believe it is a firewall issue. I can reach either server via CURL and do \_cluster/health and receive a response. I can ping both machines. ---
**Author:** ![warkolm](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/warkolm/32/39224_2.png) [@warkolm](https://discuss.elastic.co/u/warkolm)\ **Post date:** [December 24, 2015, 12:03am UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897/4 "2015-12-24T00:03:18Z")
Can you do those from each of the two nodes to the other one? ---
**Author:** ![zetian](https://avatars.discourse-cdn.com/v4/letter/z/f14d63/32.png) [@zetian](https://discuss.elastic.co/u/zetian)\ **Post date:** [December 24, 2015, 12:04am UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897/5 "2015-12-24T00:04:05Z")
yes I can do curl from either node to the other node ---
**Author:** ![warkolm](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/warkolm/32/39224_2.png) [@warkolm](https://discuss.elastic.co/u/warkolm)\ **Post date:** [December 24, 2015, 12:15am UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897/6 "2015-12-24T00:15:50Z")
Weird, are you starting both nodes at the same time, or one and then the other? ---
**Author:** ![zetian](https://avatars.discourse-cdn.com/v4/letter/z/f14d63/32.png) [@zetian](https://discuss.elastic.co/u/zetian)\ **Post date:** [December 24, 2015, 12:16am UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897/7 "2015-12-24T00:16:55Z")
One and then the other... ---
**Author:** ![zetian](https://avatars.discourse-cdn.com/v4/letter/z/f14d63/32.png) [@zetian](https://discuss.elastic.co/u/zetian)\ **Post date:** [January 1, 2016, 6:21pm UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897/8 "2016-01-01T18:21:38Z")
And... it turned out to be a firewall configuration problem. I don't know why 9200 was open and 9300 was blocked. pretty weird. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 5, 2017, 11:27pm UTC](https://discuss.elastic.co/t/unicast-cluster-nodes-fail-to-connect-v2-1-0/37897/9 "2017-07-05T23:27:32Z")