When I go to Project > Boards in my project, I get a list of all the boards. Only Epic, Stories, and Features work items appear in the Board Page dropdown. I'd like to have Issues, Test Plans, Tasks, and Bugs type work items there as well, so I don't have to go to other pages to see the same thing. But I can't seem to find any setup that will allow me to do so; could you possibly offer a technique for me to get in on single boards?
https://docs.microsoft.com/en-us/azure/devops/pipelines/agents/agents?view=azure-devops
Or take a look at this old blog article, which is where the communication section comes from:
https://devblogs.microsoft.com/devops/deploying-to-on-premises-environments-with-visual-studio-team-services-or-team-foundation-server/
The ideal approach would be to run self-hosted build agents on a server that is accessible via the internet and setup an agent pool in Azure DevOps Services for them. You'll want to use Deployment Groups for deployments and install deployment group agents on target servers, which will only need outbound 443 access to communicate with Azure DevOps Services.
If that isn't possible, you'll have to install deployment agents on the build machine, which will then see your other on-premise servers. However, this is an unsatisfactory solution because you'll either have to rely on WinRm capabilities for deployments or expose too much network between your build server and other on-premise servers.