“Hell is paved with good intentions.” - Samuel Johnson

Sometimes you come across an overachiever. Someone that thinks very highly of himself but keeps on inventing new ways to shackle you.

Idea of the day : let’s cut down the number of entries in the unix_socket_directories entry of postgresql.conf, specifically /tmp folder.

Alright now, PostgreSQL might not be the smartest ever when it comes to managing .sock files for local connections.

BUT…

If you remove the /tmp option in postgresql.conf unix_socket_directories, you will end up with this nice message from PostgreSQL when connecting :

[postgres@server ~]$ psql
psql: could not connect to server: No such file or directory
        Is the server running locally and accepting
        connections on Unix domain socket "/tmp/.s.PGSQL.5432"?

Well now you have to provide psql with either

psql -h localhost 

or

psql -h /var/run/postgresql

for example. This depending on what you find in your unix_socket_directories parameter.

So just keep the /tmp in your entry.

WHY ?

It’s the best way to insure the folder /tmp is emptied on each reboot so it’s always squeaky clean.

And above all : PostgreSQL always tries to connect only using this folder by default.

Removing entries will not help security. Other things can. Keep at least /tmp. For us DBAs. Please. This is me being polite. Or at least I am doing my best.

unix_socket_directories = '/var/run/postgresql, /var/postgres/test/9.6/run, /tmp'