# WARN netty:620 - \[node-1\] exception caught on transport layer

**URL:** <https://discuss.elastic.co/t/warn-netty-620-node-1-exception-caught-on-transport-layer/43218>\
**Category:** Elasticsearch\
**Created:** [March 2, 2016, 9:31am UTC](https://discuss.elastic.co/t/warn-netty-620-node-1-exception-caught-on-transport-layer/43218 "2016-03-02T09:31:59Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![h\_w](https://avatars.discourse-cdn.com/v4/letter/h/8baadc/32.png) [@h\_w](https://discuss.elastic.co/u/h_w)\
**Post date:** [March 2, 2016, 9:31am UTC](https://discuss.elastic.co/t/warn-netty-620-node-1-exception-caught-on-transport-layer/43218/1 "2016-03-02T09:31:59Z")

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Hello. I wonder if someone could help me with this error.  
I am trying to get cassanda + elasticsearch + usergrid up and running.

My cassandra is healthy and when I do a "curl -v localhost:9200" I get a nice reply:

{  
"name" : "node-1",  
"cluster\_name" : "elasticsearch",  
"version" : {  
"number" : "2.2.0",  
"build\_hash" : "8ff36d139e16f8720f2947ef62c8167a888992fe",  
"build\_timestamp" : "2016-01-27T13:32:39Z",  
"build\_snapshot" : false,  
"lucene\_version" : "5.4.1"  
},  
"tagline" : "You Know, for Search"  
}

- Connection #0 to host localhost left intact

However, when I start tomcat7 I see this same error recurring all the time, and I cant seem to be able to fix it:

11:26:30,935 WARN netty:620 - [node-1] exception caught on transport layer [[id: 0xca4c6d3d]], closing connection  
java.net.UnknownHostException: localhost:9200  
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:184)  
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)  
at java.net.Socket.connect(Socket.java:589)  
at org.elasticsearch.common.netty.channel.socket.oio.OioClientSocketPipelineSink.connect(OioClientSocketPipelineSink.java:109)  
at org.elasticsearch.common.netty.channel.socket.oio.OioClientSocketPipelineSink.eventSunk(OioClientSocketPipelineSink.java:69)  
at org.elasticsearch.common.netty.channel.DefaultChannelPipeline.sendDownstream(DefaultChannelPipeline.java:574)  
at org.elasticsearch.common.netty.channel.Channels.connect(Channels.java:634)  
at org.elasticsearch.common.netty.channel.AbstractChannel.connect(AbstractChannel.java:207)  
at org.elasticsearch.common.netty.bootstrap.ClientBootstrap.connect(ClientBootstrap.java:229)  
at org.elasticsearch.common.netty.bootstrap.ClientBootstrap.connect(ClientBootstrap.java:182)  
at org.elasticsearch.transport.netty.NettyTransport.connectToChannelsLight(NettyTransport.java:769)  
at org.elasticsearch.transport.netty.NettyTransport.connectToNode(NettyTransport.java:737)  
at org.elasticsearch.transport.netty.NettyTransport.connectToNodeLight(NettyTransport.java:709)  
at org.elasticsearch.transport.TransportService.connectToNodeLight(TransportService.java:154)  
at org.elasticsearch.discovery.zen.ping.unicast.UnicastZenPing$3.run(UnicastZenPing.java:376)  
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)  
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)  
at java.lang.Thread.run(Thread.java:745)

Tomcat wont start up, and I wonder if it is because of this error.

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**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:** [March 2, 2016, 9:51am UTC](https://discuss.elastic.co/t/warn-netty-620-node-1-exception-caught-on-transport-layer/43218/2 "2016-03-02T09:51:12Z")

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You're running ES in Tomcat? That's not a good idea.

Also do you have `localhost:9200` somewhere in your config?

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**Author:** ![h\_w](https://avatars.discourse-cdn.com/v4/letter/h/8baadc/32.png) [@h\_w](https://discuss.elastic.co/u/h_w)\
**Post date:** [March 2, 2016, 9:57am UTC](https://discuss.elastic.co/t/warn-netty-620-node-1-exception-caught-on-transport-layer/43218/3 "2016-03-02T09:57:38Z")

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Hey!

On tomcat I am running the usergrid .WAR.  
UserGrid has a deploymen configuration file where reference is made to ES like this:

elasticsearch.cluster\_name=elasticsearch  
elasticsearch.hosts=localhost:9200

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**Author:** ![magnusbaeck](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/magnusbaeck/32/44943_2.png) [@magnusbaeck](https://discuss.elastic.co/u/magnusbaeck)\
**Post date:** [March 8, 2016, 10:41am UTC](https://discuss.elastic.co/t/warn-netty-620-node-1-exception-caught-on-transport-layer/43218/4 "2016-03-08T10:41:49Z")

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Judging by the error message elasticsearch.hosts should contain hostnames, not hostname:port tuples.

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**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, 11:10pm UTC](https://discuss.elastic.co/t/warn-netty-620-node-1-exception-caught-on-transport-layer/43218/5 "2017-07-05T23:10:25Z")

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