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Janak Shrestha
Janak Shrestha

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Docker Ports Mapping

#docker #portsmapping

The Nautilus DevOps team is planning to host an application on a nginx-based container. There are number of tickets already been created for similar tasks. One of the tickets has been assigned to set up a nginx container on Application Server 1 in Stratos Datacenter. Please perform the task as per details mentioned below:

a. Pull nginx:stable docker image on Application Server 1.

b. Create a container named cluster using the image you pulled.

c. Map host port 8089 to container port 80. Please keep the container in running state.

Connect to App Server 1 

ssh tony@stapp01
sudo -i
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Password for tony: Ir0nM@n

Pull the nginx:stable Image 

docker pull nginx:stable
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The image was pulled successfully with digest sha256:a7675fcee220f59b4a99f7098c06a0d5d999c2c0ee37c0211efb780536e5cb20.

Verify the image:

docker images | grep nginx
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Output:

nginx        stable    2cbc7a375718   6 days ago   162MB
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Create the Container with Port Mapping 

docker run -d --name cluster -p 8089:80 nginx:stable
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The container was created with ID be82a3c468a5.

Verify the Container is Running 

docker ps | grep cluster
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Output:

be82a3c468a5   nginx:stable   "/docker-entrypoint.…"   8 seconds ago   Up 7 seconds   0.0.0.0:8089->80/tcp, :::8089->80/tcp   cluster
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The container cluster is running and port 8089 is mapped to container port 80.

Verify the Port Mapping 

docker port cluster
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Output:

80/tcp -> 0.0.0.0:8089
80/tcp -> [::]:8089
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Alternative verification:

docker inspect cluster --format='{{range $p, $conf := .NetworkSettings.Ports}}{{$p}} -> {{(index $conf 0).HostPort}}{{end}}'
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Output:

80/tcp -> 8089
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Test the Port Mapping 

curl -I http://localhost:8089/
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Output:

HTTP/1.1 200 OK
Server: nginx/1.30.6
Date: Tue, 27 Oct 2026 11:18:14 GMT
Content-Type: text/html
Content-Length: 896
Last-Modified: Fri, 02 Oct 2026 14:33:28 GMT
Connection: keep-alive
ETag: "6abfc0b8-380"
Accept-Ranges: bytes
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The HTTP 200 OK response confirms the nginx container is accessible on host port 8089.

Complete Command Sequence 

ssh tony@stapp01
sudo -i

docker pull nginx:stable

docker run -d --name cluster -p 8089:80 nginx:stable

docker ps | grep cluster
docker port cluster
curl -I http://localhost:8089/
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