[Django]-Can't run the server on Django (connection refused)

For me it was for postgres not being started and enabled. So I solved the problem by doing so:

sudo systemctl start postgresql
sudo systemctl enable postgresql

Make port default to 5432

DATABASES = {
'default': {
    'ENGINE': 'django.db.backends.postgresql_psycopg2',
    'NAME': 'database1',                      
    'USER': 'root',
    'PASSWORD': '123456',
    'HOST': 'localhost',
    'PORT': '5432',
    }
}

run the command:

python manage.py runserver 127.0.0.1:8000

I just had the same problem and I just had forgotten to start my Postgres. Opening it from my Applications and selecting “Open psql” solved the problem.

If you are using Postgresql and developing on a mac then you can use the below command to start Postgresql and it should fix your problem.

pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log start

and to stop it

pg_ctl -D /usr/local/var/postgres stop -s -m fast

Try removing host and port:

# settings.py

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql',
        'NAME': 'db_name',
        'USER': 'db_user',
        'PASSWORD': 'db_pass',
    }
}

The problem for me was specifying HOST and/or PORT here.

I faced a similar issue and I solved it by changing the value of "HOST": "localhost" to "HOST": "127.0.0.1" and it worked.

Credit to Addicted above. I checked the log and realized at some point I had upgraded my Postgres version.

$ nano server.log

  GNU nano 2.0.6                               File: server.log                                                                     

2020-12-16 02:19:32.273 EST [32414] FATAL:  database files are incompatible with server
2020-12-16 02:19:32.273 EST [32414] DETAIL:  The data directory was initialized by PostgreSQL version 12, which is not compatible with this version 13.0.

Which can be solved like this.

no database server is hosted and running locally. For mac, you can turn on a server on port 5432 using the postgres desktop application.

I Had the same problem but in my case its due to memory shortage.
Due to memory shortage the postgresql was not able to create the file .s.PGSQL.5432 inside /var/run/postgresql/.
So Look for the memory storage and if there is no memory available ,please free some memory and try restarting postgresql service.

I had the same problem because I forgot to run docker.