Why I get the error: Ident authentication failed for user 'abelard' under Cent OS 6, PostgreSQL 9.4

[Dillon Peng]

All config files described here are the same as my Mac OS's and all works fine in Mac OS.

 

I got the same error in CentOS 6 x86_64:

 

    Ident authentication failed for user 'abelard'

When running the following two commands:

    1. rake db:create

    2. psql -d testforabelard2 -U abelard -h localhost

I got the same error after trying these answers [1](http://stackoverflow.com/a/8102547/1054800) and [2](http://stackoverflow.com/a/2942678/1054800).

My `/var/lib/pgsql/9.4/pg_hba.con`'s content is as follows:

    local   all             all                                     trust

    host    all             all             127.0.0.1/32            trust

    host    all             all             ::1/128                 trust

And there is a blank file `/var/lib/pgsql/9.4/pg_ident.con`

My `database.yml`'s content is as follows:

    development:

      adapter: postgresql

      encoding: unicode

      database: social_stream_development

      pool: 5

      username: abelard

      password: password

And for offering the same params as my Mac OS's, I altered `PostgreSQL`'s user `abelard` :

    testforabelard2=# \du

                List of roles

     Role name | Attributes  | Member of 

    -----------+-------------+-----------

     abelard   | Superuser   | {}

               : Create role   

               : Create DB     

     postgres  | Superuser   | {}

               : Create role   

               : Create DB   

And I can run the command without `-h localhost` successfully:

    

    psql -d testforabelard2 -U abelard

I don't know what things I miss, any advice will be welcome!