[Bug] Why are there a large number of auto-forwarded ports in the dev container

[tschaffter]

Is there an existing issue for this?

• [X] I have searched the existing issues

What product(s) are you seeing the problem on?

Sage Monorepo

Current behavior

I removed all Docker artifact on the host and then rebuilt and opened the monorepo in a new dev container. VS Code is showing a large number of ports (96). Most of them are auto-forwarded and not active.

The following processes are using non-labeled ports:

• 34355: SonarLint (VS Code extension)
• 37815: Gradle server (VS Code extension)
• 64120: SonarLint but different process than the one listed above (VS Code extension)

One of the non-labelled port is also blocking AWS VPN. Closing VS Code enables the AWS VPN to connect again.

My guess is that these two processes starts on random ports. I think that I've also seen more than one gradle server running at a time and so the second server probably started on a different port.

Task:

• Is VS Code remembering the list of ports forwarded?

Expected behavior

No response

Anything else?

No response

Commit ID

No response

Are you developing inside the dev container?

• [X] I am using the dev container

Code of Conduct

• [X] I agree to follow this project's Code of Conduct

[tschaffter]

Closing all the non-labeled ports that are not linked to a process solved the issue with AWS VPN. So even if there are no processes listening to a port, VS Code is still forwarding it, which makes it unusable on the local host.

[tschaffter]

Number of ports forwarded by VS Code after several closing & opening VS Code, which automatically reopen the dev container.

• 38
• 39
• 40

Each time VS Code is started, the gradle server is listening to a different server.

[tschaffter]

The Angular app with SSR is starting a node process that listed to different (random?) non-labeled port:

$ nx serve-ssr openchallenges
...
base URL: http://localhost:39801

$ nx serve-ssr openchallenges
...
base URL: http://localhost:46597

[tschaffter]

Here is the port/an example of port used by AWS VPN: http://127.0.0.1:35001

[tschaffter]

Gradle servers

Gradle servers created by the VS Code extension use non-labelled ports. BUT the forwarded ports are removed once the server are no longer running, which is great.

[tschaffter]

Node server used by Angular app

The node server listens to what seems a random port. The port forwarded by VS Code is removed when the node server is stopped.