posgresql无法连接到：意外的错误，同时处理的请求：无法连接到服务器：没有这样的文件或目录

Question

我下面亚马逊EC2面临的一个很奇怪的问题，PostgreSQL是错误：

Unexpected error while processing request: could not connect to server: No such file or directory 
    Is the server running locally and accepting 
    connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"? 

    /bundle/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:671:in `initialize' 
    /bundle/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:671:in `new' 
    /bundle/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:671:in `connect' 
    /bundle/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:217:in `initialize' 
    /bundle/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:37:in `new' 
    /bundle/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:37:in `postgresql_connection' 

我可以通过psql通过psql命令登录到AWS EC2实例，但是当它使用我的Rails应用程序时，它不起作用，可能是什么问题？

我为我的应用程序部署使用AWS + EC2 + Docker + RDS。

的database.yml

default: &default 
    adapter: postgresql 
    encoding: unicode 
    pool: 5 
    timeout: 5000 

development: 
    <<: *default 
    database: <%= Figaro.env.rds_db_name || Figaro.env.database_name %> 
    host: <%= Figaro.env.rds_hostname || Figaro.env.database_host %> 
    port: <%= Figaro.env.rds_port || Figaro.env.database_port %> 
    username: <%= Figaro.env.rds_username || Figaro.env.database_username %> 
    password: <%= Figaro.env.rds_password || Figaro.env.database_password %> 

test: 
    <<: *default 
    database: cluetap_test 

dev: 
    <<: *default 
    database: <%= Figaro.env.database_name %> 

staging: 
    <<: *default 
    database: <%= Figaro.env.rds_db_name || Figaro.env.database_name %> 
    host: <%= Figaro.env.rds_hostname || Figaro.env.database_host %> 
    port: <%= Figaro.env.rds_port || Figaro.env.database_port %> 
    username: <%= Figaro.env.rds_username || Figaro.env.database_username %> 
    password: <%= Figaro.env.rds_password || Figaro.env.database_password %> 

production: 
    <<: *default 
    database: <%= Figaro.env.rds_db_name || Figaro.env.database_name %> 
    host: <%= Figaro.env.rds_hostname || Figaro.env.database_host %> 
    port: <%= Figaro.env.rds_port || Figaro.env.database_port %> 
    username: <%= Figaro.env.rds_username || Figaro.env.database_username %> 
    password: <%= Figaro.env.rds_password || Figaro.env.database_password %> 

Answer 1

这是与安全组的问题，所以我已经更新它，然后它工作正常。