PostgreSQL Setup and Configuration on Docker

 

Install PostgreSQL Database on Docker

 

Run the command in terminal to install PostgreSQL in Docker(map a port).

 

docker run --name some-postgres -e POSTGRES_PASSWORD=secret -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

 

I have described the option explanation below :-

--name                   - The container name

-e                          - It refers to Postgres User name and password

-d                          - I will run in Detached mode (background) . if you run it without using it, the docker container will be stopped when you press the Ctrl + C combination or close the terminal screen. This is uncommon because the container should be running in the background.

-p                         - 5432 port is used by default . but it can be changed this according to preference. Local port and container port can be set separately. The first port is for local, and the second for container.

Postgres               - image name

To test: Run the postgres database (command below).

 

Now connect to container using container id :-

docker exec -it 5556f4c78c1f bash

 

 Go inside your container and create a database:

root@05b3a3471f6f:/# psql -U postgres

postgres-# CREATE DATABASE mytest;

postgres-# \q

  Now connect to container using container id :-

 

postgres=# \q

root@5556f4c78c1f:/# hostname -i

172.17.0.2

root@5556f4c78c1f:/#

 

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

 

How to connect to PostgreSQL in docker container from outside #

First, check the container id:

 

root@worldpgdb:~# docker ps

CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS               NAMES

5556f4c78c1f        postgres            "docker-entrypoint.s…"   3 days ago          Up 3 days           5432/tcp            some-postgre

root@worldpgdb:~#

Suppose, if we want to verify the Ubuntu version from the container image the below steps we need to follow:

first, connect to the container using container ID 

Then, check the release version from /etc/*release* as below commands 

 

 

Remove container image from docker by step by step:

The below commands to delete the container which is no longer used

 

Since it is (image id "b97bae343e06") referenced to multiple repositories, we have to use the force option to delete the image permanently which I verified was not working. 

Now the image is successfully deleted with the force option.