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Connecting to Postgresql in a docker container from outside

I have Postgresql on a server in a docker container. How can I connect to it from the outside, that is, from my local computer? What setting should I apply to allow that?

what command did you use to start the postresql? you're able to expose a port and map it

M
Massimiliano Kraus

You can run Postgres this way (map a port):

docker run --name some-postgres -e POSTGRES_PASSWORD=mysecretpassword -d -p 5432:5432 postgres

So now you have mapped the port 5432 of your container to port 5432 of your server. -p <host_port>:<container_port> .So now your postgres is accessible from your public-server-ip:5432

To test: Run the postgres database (command above)

docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                     NAMES
05b3a3471f6f        postgres            "/docker-entrypoint.s"   1 seconds ago       Up 1 seconds        0.0.0.0:5432->5432/tcp    some-postgres

Go inside your container and create a database:

docker exec -it 05b3a3471f6f bash
root@05b3a3471f6f:/# psql -U postgres
postgres-# CREATE DATABASE mytest;
postgres-# \q

Go to your localhost (where you have some tool or the psql client).

psql -h public-ip-server -p 5432 -U postgres

(password mysecretpassword)

postgres=# \l

                             List of databases
   Name    |  Owner   | Encoding |  Collate   |   Ctype    |   Access privileges
-----------+----------+----------+------------+------------+-----------------------
 mytest    | postgres | UTF8     | en_US.utf8 | en_US.utf8 |
 postgres  | postgres | UTF8     | en_US.utf8 | en_US.utf8 |
 template0 | postgres | UTF8     | en_US.utf8 | en_US.utf8 | =c/postgres   

So you're accessing the database (which is running in docker on a server) from your localhost.

In this post it's expained in detail.


@Tjorriemorrie You're sure your postgres is running on your local machine? Maybe try 127.0.0.1 instead of localhost but for met it's working.
Get your public IP address (osx): ifconfig -u | grep 'inet ' | grep -v 127.0.0.1 | cut -d\ -f2 | head -1
Of all of the various postgres/docker related posts I have found this is one of the most useful. Thank you.
@GarouDan if you don't want to map a port but still want to access the postgres container from your host you'll need to deploy your container on the host network like this: docker run --net=host --name some-postgres -e POSTGRES_PASSWORD=mysecretpassword -d -p 5432:5432 postgres
exiting psql works with \q (just for the newbies like me)
C
Capripot

I managed to get it run on linux

run the docker postgres - make sure the port is published, I use alpine because it's lightweight. docker run --rm -P -p 127.0.0.1:5432:5432 -e POSTGRES_PASSWORD="1234" --name pg postgres:alpine using another terminal, access the database from the host using the postgres uri psql postgresql://postgres:1234@localhost:5432/postgres

for mac users, replace psql with pgcli


glad that someone answered how to connect without jumping into the container. thnx.
You really shouldn't use sudo to run your container.
@Thomas Webber Thank you, This worked for me
S
SuperNova

You can also access through docker exec command by:

$ docker exec -it postgres-container bash

# su postgres

$ psql

Or

$ docker exec -it postgres-container psql -U postgres

psql -U postgres
What does su postgres do?
@Breno su postgres means: switch user to the postgres user.
WORKS amazing. First you need to get the container ID of your docker postgress, use the command "docker ps -a", then use the continerID with this command: docker exec -it container_ID psql -U postgres
q
questionto42standswithUkraine

I am using django with postgres in Docker containers. in the docker-compose file, add the following:

db:
    image: postgres:10-alpine
    environment:
        - POSTGRES_DB=app
        - POSTGRES_USER=postgres
        - POSTGRES_PASSWORD=supersecretpassword
    ports:
        - "6543:5432"

This ports setting uses the port 6543 (it just needs to be different from 5432) that is accessible by your local machine. For myself, I connected DBeaver to it. this will prevent port clashes between your app request and local machine request.

At first, I got a message saying that the port 5432 is in use (which is by django app) so I couldn't access by pgAdmin or DBeaver.


I found this to be the most helpful. For people uisng docker-compose, this seems like the best way to go.
I can confirm this, also this seemingly strange setting of using a port number for the host that is different from the standard while the standard 5432 can be used further for the container at no harm. I had a Windows PostgreSQL installation which was occupying the port 5432 needed to reacht the Docker host, see Connect to dockerized postgres from Windows Docker host?.
And then which IP do you use to connect?
佚名

I'm assuming that you want to be able to view data present in your container everytime you connect to it from outside. To do this, you will have to persist data on the postgres image.

If you dont have persistant data, you will have to repeat everything you did the first time. Steps 3, 5, 6, 7, and 8 answer your question directly.

Here is the detailed overview of the entire process I followed on Windows 10 powershell (commands are the same in Linux and macOS as well):

Step 1: Start powershell in non-admin mode

Step 2: Download postgres docker image:
docker pull postgres:latest

Step 3: Start docker container in detached mode and persist data on postgres image by creating a volume and binding it to a destination
(Note: by default 5432 is the default port that is used; but state it explicitly to prevent connection errors from clients like pgadmin, dbeaver, etc.)
docker run --name postgres-test -e POSTGRES_PASSWORD=password -p 5432:5432 -v postgres-data:/var/lib/postgresql/data -d postgres:latest

Step 4: Check status of running containers
docker ps -a

Step 5: Go inside container_name in interactive mode
(Note: commands like ls, pwd, etc. can be executed here if you've checked linux containers during installation)
docker exec -it postgres-test psql -U postgres

Step 6: Create sample data. At this point, you can play with psql commands in the following manner:

# CREATE DATABASE test;
# \c test
# CREATE TABLE test_table(something int);
# INSERT INTO test_table VALUES (123);
# SELECT * FROM test_table;
# \q

Step 7: Open a database client application like pgadmin or dbeaver and enter the below in the connection fields:

Host: localhost
Database: test
User: postgres
Password: password

Step 8: Enter the query select * from test_table in the query editor and you should be able to see the output 123


I've followed this exactly, but when I enter the details in dbeaver it says the test database doesn't exist
M
Massimiliano Kraus

I already had running postgres on host machine and didn't want to allow connections from network, so I did run temporary postgres instance in container and created database in just two lines:

# Run PostgreSQL
docker run --name postgres-container -e POSTGRES_PASSWORD=password -it -p 5433:5432 postgres

# Create database
docker exec -it postgres-container createdb -U postgres my-db

if you want to create a single default database you can also add: -e POSTGRES_DB=my-db to create my-db instead of postgres
R
Rishabh Anand

I know this is late, if you used docker-compose like @Martin

These are the snippets that helped me connect to psql inside the container

docker-compose run db bash

root@de96f9358b70:/# psql -h db -U root -d postgres_db

I cannot comment because I don't have 50 reputation. So hope this helps.


Op wants to connect from outside.
@avizzzy this is just an alternative to what Ashutosh Gupta said stackoverflow.com/a/54865728/10422291 Should've commented there too. Not like I care but should be consistent in life right?
@RishabhAnand well from now you will be :)
u
user2627846

To connect from the localhost you need to add '--net host':

docker run --name some-postgres --net host -e POSTGRES_PASSWORD=mysecretpassword -d -p 5432:5432 postgres

You can access the server directly without using exec from your localhost, by using:

psql -h localhost -p 5432 -U postgres

M
Marc Perrin-Pelletier

For some reason 5432 port seems protected. I changed my port config from 5432:5432to 5416:5432 and the following command worked to connect to your postgres database from outside its docker container:

psql -h localhost -p 5416 -U <my-user> -d <my-database>

It´s works for me but I did not find an explanation on Internet. Did you find?
@negas You are probably already running the postgres service on your host machine which will already bind to localhost:5432 preventing you from using it. Mapping a different host port to the default port 5432 inside the container is a good solution to that; alternatively you could stop the postgres service on your host but perhaps it's used for something you need.
M
Martin

I tried to connect from localhost (mac) to a postgres container. I changed the port in the docker-compose file from 5432 to 3306 and started the container. No idea why I did it :|

Then I tried to connect to postgres via PSequel and adminer and the connection could not be established.

After switching back to port 5432 all works fine.

  db:
    image: postgres
    ports:
      - 5432:5432
    restart: always
    volumes:
      - "db_sql:/var/lib/mysql"
    environment:
      POSTGRES_USER: root
      POSTGRES_PASSWORD: password
      POSTGRES_DB: postgres_db

This was my experience I wanted to share. Perhaps someone can make use of it.


Volume path: /var/lib/mysql ?
5432 is Postgres default port. 3306 is MySQL default port. If you change the published port in docker-compose then any client tools you try to use to connect will also default to trying to connect to port 5432 unless you tell them to use another port.
I
Ismail

first open the docker image for the postgres

docker exec -it <container_name>

then u will get the root --root@868594e88b53:/# it need the database connection

psql postgresql://<username>:<databasepassword>@postgres:5432/<database>

c
cora

Connect to a local container running postgres

Install psql

brew search postgres

brew install postgresql

2.

docker run --name postgres -e POSTGRES_DB=users \
  -e POSTGRES_USER=john \
  -e POSTGRES_PASSWORD=password \
  -p 5432:5432 -d postgres

psql --host=localhost --username=john --dbname=users

J
Joel Mata

This one worked for me:

PGPASSWORD=postgres psql -h localhost -p 3307 -U postgres -d postgres

Use the above to load an initial script as:

PGPASSWORD=postgres psql -h localhost -p 3307 -U postgres -d postgres < src/sql/local/blabla.sql

Do not that i remap my ports as:

docker run -p3307:5432 --name postgres -e POSTGRES_PASSWORD=postgres -d postgres

S
SuperNova

In case, it is a django backend application, you can do something like this.

docker exec -it container_id python manage.py dbshell

C
CageE

There are good answers here but If you like to have some interface for postgres database management, you can install pgAdmin on your local computer and connect to the remote machine using its IP and the postgres exposed port (by default 5432).


y
yuriyni.com

After building my gateway-microservice application i had the same issue. Can not to connect to contenerized postgresql from Heidisql.

At this moment i have solved it by simply specifying postgresql password to docker-compose.yml as well as port.

So you should find and open docker-compose.yml. Then you should enter POSTGRES_PASSWORD (don`t let it to be empty), and specify the port “5432:5432”

services: microservice33-postgresql: environment: - POSTGRES_USER=microservice33 - POSTGRES_PASSWORD=wwww - POSTGRES_HOST_AUTH_METHOD=trust ports: - 5432:5432

link for reference and screenshots post


A
Afshin Ghazi

docker ps -a to get container ids then docker exec -it psql -U -W