Why can't connect to psql?

Question

PostgreSQL

Help me please.
pg_hba.conf

# TYPE  DATABASE        USER            ADDRESS                 METHOD

# "local" is for Unix domain socket connections only
local   all             all             0.0.0.0                 password
# IPv4 local connections:
host    all             all             0.0.0.0                 password
# IPv6 local connections:
host    all             all             ::1/128                 md5

$ sudo -i -u postgres 
$ psql
$ psql: could not connect to server: No such file or directory
  Is the server running locally and accepting
  connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?

Answer 1

I don't remember what changed. pg_hba.conf I now have this:
It is important not password but md5

Answer 2

netstat -tnlp Is
postgresql running?
if not, run
/etc/init.d/postgresql start
If it doesn't start there is a log
cat /var/lib/postgresql/pgstartup.log

Answer 3

/var/run/postgresql/.s.PGSQL.5432 check for this file. The default can be 5433. To add 32 in the psql settings change the port.

Answer 4

Check if a local socket (/var/run/postgresql/.s.PGSQL.5432) was created when running postges or if it has a different name. Also check the permissions on it.
Check in the config where and how this object should be created.