connecting from trac: "no route to host" error

Dear All

I am trying to set up trac with postgresql.  However, in trac-admin
initenv I am receiving a "no route to host" error:


Database connection string [sqlite:db/trac.db]>
postgres://tdb_user:tdb_pass@locahost/tdb_dbname

Creating and Initializing Project
Initenv for '/opt/trac/pgtest' failed.
Failed to create environment.
could not connect to server: No route to host
     Is the server running on host "locahost" and accepting
     TCP/IP connections on port 5432?

Traceback (most recent call last):
   File "build/bdist.linux-x86_64/egg/trac/admin/console.py", line 413,
in do_initenv
     options=options)
   File "build/bdist.linux-x86_64/egg/trac/env.py", line 221, in __init__
     self.create(options)
   File "build/bdist.linux-x86_64/egg/trac/env.py", line 410, in create
     DatabaseManager(self).init_db()
   File "build/bdist.linux-x86_64/egg/trac/db/api.py", line 87, in init_db
     connector.init_db(**args)
   File "build/bdist.linux-x86_64/egg/trac/db/postgres_backend.py", line
98, in init_db
     params)
   File "build/bdist.linux-x86_64/egg/trac/db/postgres_backend.py", line
87, in get_connection
     params)
   File "build/bdist.linux-x86_64/egg/trac/db/postgres_backend.py", line
203, in __init__
     port))
OperationalError: could not connect to server: No route to host
     Is the server running on host "locahost" and accepting
     TCP/IP connections on port 5432?


trac-admin is happy with sqlite.
I can login to postgresql using psql.
I have disabled iptables and selinux (It's all on a centos machine).
Stopping my web server (nginx) makes no difference.

ping localhost works but indeed ping localhost 5432 does not (receives
no packets).  However, postgresql.conf has:

listen_addresses = 'localhost'
port = 5432

I have the feeling I'm missing something obvious (I have read the FAQ,
Googled, etc.).  Please can anyone advise?

With thanks and best wishes

Ivan

--
============================================================
Ivan A. Uemlianin
Speech Technology Research and Development

                     ivan@llaisdy.com
                      www.llaisdy.com
                          llaisdy.wordpress.com
                      www.linkedin.com/in/ivanuemlianin

     "Froh, froh! Wie seine Sonnen, seine Sonnen fliegen"
                      (Schiller, Beethoven)
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