Docker Error Bind: Address Already In Use

Docker is a tool to containerize the application along with its dependencies. Sometimes running an application using Docker can create some errors like docker error bind: address already in use. Here in this article, I have first discussed what is Docker. Then I have discussed when the docker error bind: address already in use occurs. Also, i have shared some steps to create this error on your system. After this i have walked you through the different steps to solve this docker error bind: address already in use.

What is Docker?

Docker is a containerization tool that encapsulates the application with all its dependencies into a compact unit called a Docker container. These docker containers contain all the important tools, code, runtime, and other necessary dependencies to run the application. Developers first write a Dockerfile for the application. Here in this Dockerfile base image, the working directory, commands to install packages, and commands to run the application are mentioned. Then this Dockerfile is built using the docker build command to generate a docker image. The docker image is very lightweight and portable. Now developers can run the application using the docker image on any system but the only condition is to install docker on that system. Docker containers use fewer resources of the host to run. As a result, multiple docker containers can run a single host machine. This results in maximum resource utilization of the host machine and also it decreases the overall infrastructure cost. Overall we can say docker has become a very important tool for organizations in software application deployments and delivery pipelines.

Pre-requisites

Before moving to the next section make sure that you have installed Docker on your system. If Docker is not installed then follow these detailed geeks for geeks articles to install Docker on your system.

• For Ubuntu users: How To Install and Configure Docker in Ubuntu?
• For Windows users: Docker – Installation on Windows

When Docker Error bind: Address Already In Use Occurs?

If you have encountered docker error bind: address already in use, this means the port you are trying to bind with docker container port is already been used by some other application or process on your system. The port that is used to connect the container from the host is already in use by some other processes.

You can follow the steps below to generate this error :

Step 1: First run a docker container. Here I have used nginx image to create a docker container. Here port forwarding is used to forward the traffic from host port 8080 to container port 80.

docker run -d -p 8080:80 --name nginx nginx:latest

Step 2 : Now run another container . Here i have used tomcat image to create a docker container . Port forwarding is used to forward the traffic at host port 8080 to tomcat container port 8080 .

docker run -d -p 8080:8080 --name tomcat tomcat:latest

After running the command you will see an error on the terminal .

To resolve this error follow the next section .

How To Resolve Docker Error bind: Address Already In Use ?

Here follow the steps below one by one to solve the error .

Step 1 : Stop the docker container which is producing the error .

docker stop tomcat (if you have used any other container name then you should use that name instead of tomcat ) 

Step 2 : Remove the docker container

docker remove tomcat

Step 3 : Use any other unused host port and again the create the container using the below command.

docker run -d -p 8078:8080 --name tomcat tomcat:latest  (make sure your 8078 port is not used by any other process)

Step 4: You can access the tomcat server using port 8078 .

You can also access the nginx server at port 8080 .

Conclusion

Here in this guide you have first learned about what is Docker . Then you have learned when the docker error bind : address already in use occurs . You have also followed the steps to create the error by creating conflict at host port 8080 . Later in the next section you have finally learned how to resolve the docker error bind : address already in use .

Docker Error Bind : Address Already In Use – FAQ’s

Could running another container with same name as an existing container will produce error ?

Yes running another container with existing container name will produce error due to name conflict on docker .

What are reasons for port conflicts ?

Port conflicts occurs when multiple docker containers or system process tries to access same port .

How docker conflicted ports can be removed ?

You can just stop and remove the docker container to remove the conflicted port .

What is function of base image in a Dockerfile ?

Base image in a Dockerfile provides the environment to execute the later layers and commands used in the Dockerfile .

What will be consequence of ignoring ‘docker error bind : address already in use’ ?

You will face service downtime and you can not access the docker container if you ignore ‘docker error bind : address already in use‘ .