How to connect IntelliJ's Docker plugin to Docker Desktop Windows - docker

Question

I'm running the latest Windows 10 Pro build (1903), the latest Docker Engine build (v19.03.8), and the latest IntelliJ (2019.3.4). I have set Expose daemon on tcp://localhost:2375 without TLS and Apply/Restart-ed the Engine. Trying to switch to a Windows container seemingly hangs the daemon, throwing an error, after which I need to destroy all settings and config files before I can start the daemon again.
Yet, when I'm trying to set tcp://localhost:2375 in my Docker plugin, the connection simply fails (probably with a timeout, but there's no log of it). Yet, simply using docker info and other commands from the CLI works as intended, so I'm fairly certain the Engine is running.
For reference, the output of docker info:
$ docker system info
Client:
Debug Mode: false
Plugins:
app: Docker Application (Docker Inc., v0.8.0)
buildx: Build with BuildKit (Docker Inc., v0.3.1-tp-docker)
Server:
Containers: 0
Running: 0
Paused: 0
Stopped: 0
Images: 0
Server Version: 19.03.8
Storage Driver: overlay2
Backing Filesystem: <unknown>
Supports d_type: true
Native Overlay Diff: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host ipvlan macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 7ad184331fa3e55e52b890ea95e65ba581ae3429
runc version: dc9208a3303feef5b3839f4323d9beb36df0a9dd
init version: fec3683
Security Options:
seccomp
Profile: default
Kernel Version: 4.19.76-linuxkit
Operating System: Docker Desktop
OSType: linux
Architecture: x86_64
CPUs: 2
Total Memory: 1.943GiB
Name: docker-desktop
ID: NGP3:BQCE:JSUO:6BSV:IUU6:2UEZ:4QTQ:N6IO:TA3T:A7I7:4GXS:IYD6
Docker Root Dir: /var/lib/docker
Debug Mode: true
File Descriptors: 34
Goroutines: 50
System Time: 2020-03-27T15:56:23.690394533Z
EventsListeners: 3
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: false
Product License: Community Engine
What else can I try (short of using Docker Toolkit again) to get the integration up and running? How can I even test where the connection might be dropping?

Answer 1

So after three days of research, I have an answer. Apparently, Windows 10 reserves a port range of 2344-2444, which prevents the Docker daemon from actually exposing the TCP socket, despite the settings. I have a feeling it also relates to the daemon being unable to start after a reboot. You can verify if this is the root cause of the issue by executing the following in an elevated prompt/powershell: netsh interface ipv4 show excludedportrange protocol=tcp - if the output show a range that includes 2375, you are affected,
Remediation (this will include two reboots!):
Disable HyperV and reboot, to free up the port allocations: dism.exe /Online /Disable-Feature:Microsoft-Hyper-V
Manually allocate port 2375: netsh int ipv4 add excludedportrange protocol=tcp startport=2375 numberofports=1
Re-enable HyperV and reboot to take advantage of the fix: dism.exe /Online /Enable-Feature:Microsoft-Hyper-V /All
Optional: after this process, you can re-enable TLS on said socket, and the Docker plugin will be able to connect just fine.

Answer 2

2 years later (June 2022), this integration is easier to setup, assuming you have the latest Docker Desktop for Windows.
It uses as a back-end either WSL2 or HyperV.
The article "Getting Started with Visual Studio Code and IntelliJ IDEA Docker Plugins" from Tyler Charboneau details the IntelliJ IDEA part.
It will require a manual installation of the Docker plugin if you’re using the Community Edition.
Once you’ve installed the Docker plugin, you’ll need to connect it to Docker Desktop.
Follow these steps:
Navigate to IntelliJ IDEA > Preferences.
Expand the Build, Execution, Deployment group.
Click Docker, and then click the small "+" icon to the right.
Choose the correct Docker daemon for your platform (for example, Docker for Mac).
The installation may take a few minutes. Once it’s complete, you’ll see the "Connection successful" message toward the middle-bottom of the Preferences pane: