Docker Login with Sonatype's Nexus

Sonatype's Nexus is an artifact repository for a variety of formats (e.g., Maven, npm, Nuget, etc.), but I use it primarily for Docker. I cache all the images that I use1 not only for speed but also to keep a copy that I can control the life of. Once it's set up, it usually enters into that "forget it" step. However for dumb-dumb reasons of my own doing, I needed to re-configure my install. I ran into this last time, and I ran into it again this time. For a hot minute, I could not login to the repository from via docker login; I kept getting a 401 Unauthorized. From the last time I set it up, I remembered there was something completely unintuitive that I needed to do. I figured it out again, and it takes less than 30 seconds to fix. Why Sonatype doesn't set this up automatically when you add a Docker repo, I don't know. Anyways, for both you and future!me: You have to mark the Docker Bearer Token Realm as Active. To do so, Login as an administrator. Click Settings, then expand the…