This assumes you have installed Docker on Linux and Docker is running.

A Docker image contains the code used to create a Docker container, such as creating a Nginx web server, or a mySQL server, or a home grown app, and the list goes on. In this way, an image is like a template used to create a container. An image is kind of like a virtual machine, but much more light weight, using significantly less storage a memory (containers are usually megabytes in size).

The docker pull command can be used to pull down the Kong and Postgres database images.

docker pull kong/kong-gateway
docker pull library/postgres

Or you could create Dockerfile so that the Dockerfile contains something like this.

FROM kong/kong-gateway

Then use the docker build command to create the image, running this command in the same directory as the Dockerfile.

docker build . --tag kong:latest

The docker images command can then be used to confirm the Kong and Postgres images were pulled down.

~]# docker images
REPOSITORY         TAG     IMAGE ID      CREATED       SIZE
kong/kong-gateway  latest  105b54dc64f1  32 hours ago  310 MB
postgres           latest  29dd0a82ea20  2 weeks ago   315 MB

The docker network create command can be used to create a dedicated bridge network for Kong.

docker network create kong-network

The docker network ls command can be used to confirm the dedicated Kong bridge network was created.

~]# docker network ls
NETWORK ID     NAME              DRIVER    SCOPE
7e6e54bde697   kong-network      bridge    local

The docker run command can be used to create and start a PostgresSQL database container.

• The --name option is used to name the container kong-postgres
• The --network option is used to use the kong-network
• The --publish option is used to configure the Docker server and Postgres container to listen on port 5432
• The --env option is used to define variables
• The --restart unless-stopped option is used so that the container is started if the Docker server is restarted
• The postgres:latest image is used

docker run 
--detach 
--name kong-postgres-database 
--network kong-network 
--publish 5432:5432 
--env POSTGRES_DB=kong 
--env POSTGRES_USER=kong 
--env POSTGRES_PASSWORD=itsasecret
--restart unless-stopped
postgres:latest

The docker container ls command can be used to confirm the Postgres container is up and running.

~]# docker container ls -a
CONTAINER ID   IMAGE          COMMAND                  CREATED              STATUS                          PORTS                    NAMES
a8ad22fabc22   postgres       "docker-entrypoint.s…"   6 minutes ago        Up About a minute               0.0.0.0:5432->5432/tcp   kong-postgres         

The docker exec command can be used to confirm that you are able to interact with the Postgres database in the container using the Postgres psql command.

~]# docker exec kong-postgres-database psql --version
psql (PostgresSQL) 13.4 (Debian 13.4-1.pgdg100+1)

Prepare the Postgres database.

docker run 
--rm 
--network kong-network
--env KONG_DATABASE=postgres
--env KONG_PG_HOST=kong-postgres-database
--env KONG_PG_PASSWORD=itsasecret
--env KONG_PASSWORD=itsasecret
kong/kong-gateway:latest 
kong migrations bootstrap

Create the start the Kong gateway container.

docker run
--detach
--name kong
--network kong-network
--env KONG_DATABASE=postgres
--env KONG_PG_HOST=kong-postgres-database
--env KONG_PG_PASSWORD=itsasecret
--env KONG_ADMIN_ACCESS_LOG=/dev/stdout
--env KONG_ADMIN_ERROR_LOG=/dev/stderr
--env KONG_ADMIN_LISTEN=0.0.0.0:8001
--env KONG_ADMIN_GUI_URL=http://<hostname or ip address Docker server>:8002
--env KONG_PASSWORD=itsasecret
--env KONG_PROXY_ACCESS_LOG=/dev/stdout
--env KONG_PROXY_ERROR_LOG=/dev/stderr
--publish 8000:8000
--publish 8001:8001
--publish 8002:8002
--publish 8003:8003
--publish 8004:8004
--publish 8443:8443
--publish 8444:8444
--publish 8445:8445
--restart unless-stopped
kong/kong-gateway:latest

The docker container ls command can be used to confirm the Postgres and Kong containers are up and running.

~]$ sudo docker container ls -a
CONTAINER ID   IMAGE                      COMMAND                  CREATED          STATUS                    PORTS                                                                                                                                                   NAMES
593607ba5a19   kong/kong-gateway:latest   "/docker-entrypoint.…"   14 seconds ago   Up 13 seconds (healthy)   0.0.0.0:8000-8003->8000-8003/tcp, :::8000-8003->8000-8003/tcp, 8004/tcp, 0.0.0.0:8443-8445->8443-8445/tcp, :::8443-8445->8443-8445/tcp, 8446-8447/tcp   kong
93c1a7f163a7   postgres                   "docker-entrypoint.s…"   16 minutes ago   Up 16 minutes             0.0.0.0:5432->5432/tcp                                                                                                                                  kong-postgres

You should now be able to access the Kong GUI at http://<hostname or ip address Docker server>:8002.

And the following command should return JSON containing the current status of Kong.

curl --request GET http://<hostname or ip address Docker server>:8001/status