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Running PostgreSQL in Docker

This walks you through:

  1. Running Postgres locally in a docker container using docker networking (rather than the deprecated container links functionality that is mentioned in the Postgres Docker instructions.
  2. Deploying to Docker Cloud

Basic Postgres container with docker networking

Create a user defined network

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$ docker network create --driver bridge postgres-network

Launch Postgres in that network

The main parameter you will need to provide to postgres is a root db password. Replace ********* with a good password and run this command:

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$ docker run --name postgres1 --network postgres-network -e POSTGRES_PASSWORD=********* -d postgres

Launch psql and connect to Postgres

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$ docker run -it --rm --network postgres-network postgres psql -h postgres1 -U postgres
Password for user postgres: <enter password used earlier>
psql (9.6.3)
Type "help" for help.

postgres=#

You now have a working postgres database server.

Using a mounted volume for persistence

When running postgres under docker, most likely want to persist the database files on the host, rather than having them in the container.

First, remove the previous container with:

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$ docker stop postgres1 && docker rm postgres1

Go into the /tmp directory:

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$ cd /tmp

Launch a container and use /tmp/pgdata as the host directory to mount as a volume mount, which will be mounted in the container in /var/lib/postgresql/data, which is the default location where Postgres stores it’s data. The /tmp/pgdata directory will be created on the host if it doesn’t already exist.

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$ docker run --name postgres1 --network postgres-network -v /tmp/pgdata:/var/lib/postgresql/data -e POSTGRES_PASSWORD=*************** -d postgres

List the contents of /tmp/pgdata and you should see several Postgres files:

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$ ls pgdata/
PG_VERSION        pg_hba.conf     pg_serial       pg_twophase ...

Launch phppgadmin Container

First create a user

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$ docker run -it --rm --network postgres-network postgres /bin/bash

Now you will be in a shell inside the docker container

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# createuser testuser -P --createdb -h postgres1 -U postgres
Enter password for new role: *******
Enter it again: ******
Password: <enter postgres password from earlier>

Launch pgpadmin

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 $ docker run --name phppgadmin --network postgres-network -ti -d -p 8080:80 -e DB_HOST=postgres1 keepitcool/phppgadmin

Login

In your browser, open http://localhost:8080/ and you should see the phpadmin login screen:

loginscreen

Login with user/pass credentials created earlier:

  • username: testuser
  • password: **********

postlogin

Deploying to Docker Cloud

Deploy Stack

Create a new stack and paste it into the box

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postgres-server:
  autoredeploy: true
  environment:
    - POSTGRES_PASSWORD=***************
  image: 'postgres:latest'
  volumes:
    - '/var/lib/postgresql/data:/var/lib/postgresql/data'
phppgadmin:
  autoredeploy: true
  environment:
    - DB_HOST=postgres-server
  image: 'keepitcool/phppgadmin:latest'
  ports:
    - '8085:80'

For example:

Docker Cloud

Create user

Find the postgres-server container and hit the Terminal menu to get a shell on that container.

Enter:

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# createuser testuser -P --createdb -h localhost -U postgres 
Enter password for new role: *******
Enter it again: *********

Login to Web UI

Find the phppgadmin service in the Docker Cloud Web UI, and look for the service endpoint, which should look something like this:

http://phppgadmin.postgres.071a32d40.svc.dockerapp.io:8085/

Login with user/pass credentials created earlier:

  • username: testuser
  • password: **********

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