As we've seen in earlier chapters, Docker leverages a combination of relatively well-known Linux networking constructs to deliver container networking. Throughout this book, we've looked at many different ways you can configure, consume, and validate Docker networking configuration. What we haven't done is outline a troubleshooting and validation methodology you can use when you run into issues. When troubleshooting container networking, it is important to understand and be able to troubleshoot each specific networking component used in delivering end-to-end connectivity. The goal of this chapter is to provide specific steps you can take when you need to validate or troubleshoot a Docker networking issue.