Panic: Failed to register the GitLab-runner, you may be having network issues

Registering a runner is the process that binds the runner with one or more GitLab instances. After you install the application, you register individual runners, or multiple runners on the same host machine, each with a different configuration, by repeating the register command. Runners are the agents that run the CI/CD jobs that come from GitLab. When you register a runner, you are setting up communication between your GitLab instance and the machine where GitLab Runner is installed. – Runners usually process jobs on the same machine where you installed GitLab Runner. However, you can also have a runner process jobs in a container, in a Kubernetes cluster, or in auto-scaled instances in the cloud.

Here are some related guides: How to install Git on macOS, How to uninstall Git on macOS, Practical Git use with mackdown, how to clone a repository and install software from GitHub on Windows, how to use AWS CodeCommit, Azure DevOps and GitHub integration for Docker and Kubernetes deployment, and how to build your first CI/CD Pipeline in Azure DevOps using ASP.Net Core Application.

TLS connections may fail or timeout for a variety of reasons and some of which are cipher suite mismatches, certificate validation errors and TLS version incompatibility just to name a few. 
- In this case, it expressly also said Network related issues, but non of these issues caused this issue funny enough. See this guide on how to install, register and start GitLab Runner on Windows, and GitLab-runner is not recognized as an internal or external command, operable program, or batch file.

I received the error below due to using a different GitLab instance URL.

Solution: Register GitLab runner with the right URL

When you bind the GitLab-runner to the right GitLab instance URL, this issue above will be eliminated.

I am aware there may also be other reasons for this error, specifically Failed to register the GitLab-runner. But this was not my case. Therefore, I have collated a list of possible resolution steps that you will need to look at when my solution above does not fix your problem.

- A firewall could be blocking the traffic from the host to GitLab. Ensure necessary firewall rules are created to mitigate this.
- Ensure you are not running the GitLab instance and the GitLab-runner on the same host. It is recommended by GitLab not do this due to performance reasons.
- You may want to update GitLab to the latest version.

I hope you found this blog post helpful. If you encounter any issues like Failed to register the GitLab-runner or if you have any questions, please let me know in the comment session.