我遇到了错误：puma捕获了此错误：无法打开TCP连接到localhost：9200（连接拒绝 - connect -connect（2）" localhost"端口9200）（faraday :::::::ConnectionFailed）在我的Rails应用程序中，Ubuntu 14.04。
以下是我在终端中弹性搜索的输出：
prashanth@prashanth-OptiPlex-390:~$ sudo service elasticsearch restart
* Starting Elasticsearch Server prashanth@prashanth-OptiPlex-390:~$ sudo service elasticsearch start
* Starting Elasticsearch Server * Already running. [ OK ]
prashanth@prashanth-OptiPlex-390:~$ curl -X GET 'http://localhost:9200'
curl: (7) Failed to connect to localhost port 9200: Connection refused
prashanth@prashanth-OptiPlex-390:~$
这是/etc/elasticsearch/elasticsearch.yml文件中的我的弹性搜索设置
network.host: 127.0.0.1
transport.tcp.port: 9200
http.port: 9200
错误描述：
Puma caught this error: Failed to open TCP connection to localhost:9200 (Connection refused - connect(2) for "localhost" port 9200) (Faraday::ConnectionFailed)
/home/prashanth/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/net/http.rb:882:in `rescue in block in connect'
/home/prashanth/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/net/http.rb:879:in `block in connect'
/home/prashanth/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/timeout.rb:91:in `block in timeout'
/home/prashanth/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/timeout.rb:101:in `timeout'
/home/prashanth/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/net/http.rb:878:in `connect'
/home/prashanth/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/net/http.rb:863:in `do_start'
/home/prashanth/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/net/http.rb:852:in `start'
/home/prashanth/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/net/http.rb:1398:in `request'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/faraday-0.10.1/lib/faraday/adapter/net_http.rb:83:in `perform_request'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/faraday-0.10.1/lib/faraday/adapter/net_http.rb:41:in `block in call'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/faraday-0.10.1/lib/faraday/adapter/net_http.rb:88:in `with_net_http_connection'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/faraday-0.10.1/lib/faraday/adapter/net_http.rb:33:in `call'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/faraday-0.10.1/lib/faraday/rack_builder.rb:139:in `build_response'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/faraday-0.10.1/lib/faraday/connection.rb:377:in `run_request'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/elasticsearch-transport-5.0.0/lib/elasticsearch/transport/transport/http/faraday.rb:23:in `block in perform_request'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/elasticsearch-transport-5.0.0/lib/elasticsearch/transport/transport/base.rb:257:in `perform_request'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/elasticsearch-transport-5.0.0/lib/elasticsearch/transport/transport/http/faraday.rb:20:in `perform_request'
/home/prashanth/.rvm/gems/ruby-2.3.1/gems/elasticsearch-transport-5.0.0/lib/elasticsearch/transport/client.rb:128:in `perform_request'
在您发布的设置中，您的HTTP和TCP端口具有相同的端口号分配
network.host: 127.0.0.1
transport.tcp.port: 9200
http.port: 9200
我建议更改transport.tcp.port并再次尝试。
尝试使用默认值，除非您已经使用了端口9300：
network.host: 127.0.0.1
transport.tcp.port: 9300
http.port: 9200
如果您仍面临问题，则可能需要打开防火墙程序上的端口。在Ubuntu上，这可能是UFW。
如果您的服务脚本具有状态函数，则可以告诉您您的Elasticsearch实例是否正确启动。如果失败，您可以使用ps aux来确定它是否正在运行。
$ sudo service elasticsearch status
或
$ ps aux | grep elasticsearch
正如类似问题中指出的那样，curl可以在不运行Elasticsearch时拒绝连接错误（来源：FARADAY :: CONNECTFAILED，CONNECTION FAILED，CONNECTION -CONNECTIND -CONNECT（2）对于" Localhost"端口9200错误的ruby Ruby在Rails上）。
您有Docker吗？对我来说，唯一的解决方案是完全启用Docker。其他，我认为问题是关于Docker使用的端口的问题。
如果您不喜欢像我这样的很多人，请删除它，然后就可以了。