Скачать или смотреть Resolving SSH Connection Issues to Docker Containers

Are you struggling with SSH connections to your Docker containers? This comprehensive guide breaks down the solution, helping you connect without password prompts.
---
This video is based on the question https://stackoverflow.com/q/65549509/ asked by the user 'splunk' ( https://stackoverflow.com/u/4188968/ ) and on the answer https://stackoverflow.com/a/65551127/ provided by the user 'Philippe' ( https://stackoverflow.com/u/2125671/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: SSH connection asks for password connecting to Docker container

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Resolving SSH Connection Issues to Docker Containers: A Step-by-Step Guide

When working with Docker containers, many developers encounter various problems related to SSH connections. One common issue is being prompted for a password when attempting to connect to a container via SSH. This can be frustrating, especially after you've configured everything, and it still doesn't seem to work. In this post, we'll explore the typical setup and provide you with a clear solution for connecting to your Docker container without encountering password prompts.

Understanding the Problem

The situation involves trying to SSH into a Docker container. You may have set up a Dockerfile with a user and SSH server, yet upon attempting to connect, you receive a password prompt. Let's break down the scenario:

The Dockerfile: Your Dockerfile specifies the creation of an Ubuntu container, installation of an SSH server, and configuration for accessing it with a user called remote_user.

Connection Attempt: When you run the command:

[[See Video to Reveal this Text or Code Snippet]]

instead of a successful login, you see messages indicating that the authentication is failing and the system asks for a password.

Understanding the flow of the SSH connection process helps us identify what might be wrong.

Common Setup in the Dockerfile

Your Dockerfile includes steps to:

Update packages and install openssh-server.

Create a user called remote_user and set a password.

Manage SSH key configurations through the .ssh directory.

Start the SSH daemon.

Here is a brief overview of relevant parts of your Dockerfile:

[[See Video to Reveal this Text or Code Snippet]]

Steps to Connect Without Password Prompts

Step 1: Port Forwarding

One critical aspect of successful SSH connection is ensuring that the SSH service is accessible from your host machine. When you're running a Docker container, you need to forward the SSH port. Modify your command to create and run the container with port mapping:

[[See Video to Reveal this Text or Code Snippet]]

In this example, we forward the container's port 22 (the default SSH port) to your host's port 222.

Step 2: SSH Command Adjustment

After successfully running the Docker container with the port mapped, you should adjust your SSH command. Use the following command to connect:

[[See Video to Reveal this Text or Code Snippet]]

Here, -p 222 specifies that SSH should connect using port 222 on localhost.

Final Thoughts

By forwarding the correct ports and adjusting the SSH command accordingly, you should be able to connect to your Docker container as remote_user without being prompted for a password. This setup ensures that you leverage your authorized keys securely.

If you still experience issues, revisit your Dockerfile and the permissions of your .ssh directory and authorized_keys file. Remember, having the right permissions is crucial for successfully using SSH keys for authentication.

Now that you've learned how to resolve this common SSH connection issue, you can confidently manage and access your Docker containers with ease!