Howto disable Postgres listening on TCP?

Question

Simply to avoid many problems in the first place I do not want my postgres server program to accept/listen to anything from any network (i.e. TCP/IP 4/6) connections.

My setup is a Postgres 9.1 on an Ubuntu 12.04 box and I thought tweeking /etc/postgresql/9.1/main/pg_hba.conf to not include those lines which commented out (see below) would cause postgres to "please not listen on network TCP/IP devices"

local all postgres trust
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
#local all all md5
# IPv4 local connections:
#host all all 127.0.0.1/32 md5
# IPv6 local connections:
#host all all ::1/128 md5

Also I know that there is the -i command line to start the postgres server with if we YES want to listen on TCP/IP . I actually seek for the opposite thing a -??? meaning NO please do NOT listen on TCP/IP.

I used a netstat -utap | grep post and it shows that postgres besides my settings in /etc/postgresql/9.1/main/pg_hba.conf is still listening on TCP/IP.

QUESTION

What did I do wrong here? How can I shut off this TCP/IP listening attitude of my Postgres server? Having only unix socket listening I am happy to the max ;)

Thank you

Addition: I also perceive that postgres establishes a UDP connection to this 127.0.0.1:38860, what would this be about?

Answer 1

Maybe it is not the finest Solution / Answer to my question, but at least it will point anybody (facing the said challenge I had in my original question)

To disable listening on TCP/IP network I used this command line option when starting the server application:

postgres [other arguments] -c listen_addresses=''

Addition: The remaining open udp 127.0.0.1:38860 connection is supposedly linked to the purpose of the the statistics collector subprocess as suggested on postgresql.org

• Daniel Vérité: listen_addresses is specified in postgresql.conf along the other server parameters. You may change it here rather than on the command line
• humanityANDpeace: @DanielVérité Your suggested is noted and correct. I think the command line form can help you override / overwrite the postgresql.conf setting in case of need (i.e. you cannot change it for file permissions).
• humanityANDpeace: @DanielVérité Can you maybe confirm that listen_addressesneeds explicitly and necessarily been set to '' to provoke "No TCP/IP Listening"? I actually thought that having pq_hba.conf without hostentries was already sufficient, which anyway I did not observe (even without host lines in pq_hba.conf it still listened at TCP/IP). Thank you!
• Daniel Vérité: Yes, listen_addresses must be used, and postgres does not guess the interfaces to listen to based on the rules in pg_hba.conf. Besides, to change listen_addresses a full restart of the server is necessary, whereas a simple reload is needed for a change in pg_hba.conf (the latter being harmless for established connections).
• humanityANDpeace: @DanielVérité Thank you for your help and confirmation. I was misled by the address column in pg_hba.conf thinking this was powerful enough to indicate to the server where to listen and where not. Thanks to you I know am aware that setting listen_addresses='' empty is the right way to go :)

Answer 2

Simple answer;

Change the listen_addresses configuration setting Here is an example;

ALTER SYSTEM SET listen_addresses TO '';

Then restart the Postgresql service

Documentation says

If the list is empty, the server does not listen on any IP interface at all, in which case only Unix-domain sockets can be used to connect to it.

• Jürgen Weigert: In modern postgres'es it is listen_addresses instead of listen_adress
• Sahap Asci: @JürgenWeigert I updated the answer
• Soerendip: ALTER: command not found am I using the right program postgres??
• Sahap Asci: @Soren AFAIK it's available after version 9.4. It's an SQL statement. User must be superuser.
• Soerendip: It has to be used with psql for example: sudo -u postgres psql -c "ALTER SYSTEM SET listen_addresses TO '*'"