NAME

postgresql-relay - multiplex all your databases to one point of origin

SYNOPSIS

postgresql-relay [options]

DESCRIPTION

postgresql-relay can be used to as a single point of origin for all your databases. Instead of having to remember (or modify in case of changes) all the names of your databases, on which machines and on which ports they are running, you only need to remember one machine and the name of the database. The postgresql-relay will then forward the connection to the proper database on the proper port of the proper server. No more changes in the hundreds of clients and scripts!

Options are:

-c configurationfile: Use this configuration file instead of /usr/local/etc/postgresql-relay.conf.
-f: Stay in the foreground, don't daemonize. The logging will be printed to stdout too.
-q: Be quiet, don't log anything
-v: Be verbose, log a lot.

CONFIGURATION FILE

Each line in the configuration file has five fields, seperated by colons:

The first field is the incoming port for clients. For the easiest configuration on the client-side, keep this all the same (say port 5432 as the standard postgresql port).

The second field is the name of the database the client wants to connect to. This doesn't have to be the name of the database on the server connecting to.

The third field is the name of the host the database is located on.

The fourth field is the port the database is listening on.

The fifth field is the name of the database to connect to.

CONFIGURATION FILE EXAMPLES

Say you have two databases, one named mail on the local machine on port 5444 and one named users on the machine foo on port 5445. The configuration file would then be:

 5432:mail:localhost:5444:mail
 5432:users:foo:5445:users

With this configuration, Postgresql-relay will listen on port 5432 and forward connections to the mail and users databases.

EXAMPLES

Start the relay with a non-standard configuration file and keep it in the foreground:

 postgresql-relay -c /usr/local/etc/postgresql-relay.conf.test -f

Now, in a different terminal, connect to to mail database:

 psql -h dbserver -p 5432 -U root mail

FILES

postgresql-relay.conf, most likely in /usr/local/etc.

SECURITY

Postgresql-relay supports tcpwrappers. For access to postgresql-relay the daemon is called postgresql. For access to a database the daemon is called postgresql-dbname.

In the following example, the localhost and the hosts in the 10/8 network have access to postgresql-relay, while only the localhost and the 10.10.10.0/8 network have access to the database 'fdc':

 postgresql : 10.0.0.0/255.0.0.0 : allow
 postgresql : 127.0.0.1 : allow
 postgresql : ALL : deny

 postgresql-mail : 10.10.10.0/255.255.255.0 : deny 
 postgresql-mail : 127.0.0.1 : allow
 postgresql-mail : ALL : deny

LOGGING

Logging goes to syslog, to the facility daemon.

NOTES

It would be best practise if the name of the machine on which postgresql-relay is running would have an alias in DNS, so that even if the machine on which postgresql-relay is running changes, the scripts don't have to be updated. A recommended name is dbrelay.

BUGS

If the communication protocol version is unknown, it should fail properly but this hasn't been tested.

AUTHOR

Edwin Groothuis, edwin@mavetju.org (http://www.mavetju.org)