Cannot connect to HuggingFace Spaces dev mode. - Stuck at "Got some output, clearing connection timeout"

Is there an existing issue for this bug?

• I have searched the existing open issues and found none that apply.
• If I find any issue of interest that is related or closed, I will included a link to it in this issue.

Required Troubleshooting Steps

• I have read and performed the troubleshooting steps
• I have tried both values of the remote.SSH.useLocalServer setting
• My issue was not covered in the Tips and Tricks linked from the Troubleshooting Wiki.
• I will include a complete copy of my Remote - SSH logs by running Remote-SSH: Show Log in the command palette or from View > Output in the menu bar

[Optional] Diagnose with Copilot

I asked @remote-ssh but it did not help

In step 2 of the troubleshooting wiki, what was the result of running the generated SSH command verbatim outside of VS Code?

I could NOT successfully SSH to the remote machine, and the error was DIFFERENT than what I saw in VS Code

Remote-SSH Log

[02:06:47.804] Log Level: 2
[02:06:47.821] SSH Resolver called for "ssh-remote+7b22686f73744e616d65223a227373682e68662e7370616365222c2275736572223a2261726b2d6b756e2d6465762d6d6f64652d707974686f6e227d", attempt 1
[02:06:47.826] remote.SSH.useLocalServer = false
[02:06:47.826] remote.SSH.useExecServer = true
[02:06:47.826] remote.SSH.bindHost = {}
[02:06:47.827] remote.SSH.showLoginTerminal = false
[02:06:47.827] remote.SSH.remotePlatform = {"107.173.180.124":"linux","XXX":"linux"}
[02:06:47.827] remote.SSH.path = 
[02:06:47.827] remote.SSH.configFile = 
[02:06:47.827] remote.SSH.useFlock = true
[02:06:47.827] remote.SSH.lockfilesInTmp = false
[02:06:47.827] remote.SSH.localServerDownload = auto
[02:06:47.827] remote.SSH.remoteServerListenOnSocket = false
[02:06:47.827] remote.SSH.defaultExtensions = []
[02:06:47.827] remote.SSH.defaultExtensionsIfInstalledLocally = []
[02:06:47.828] remote.SSH.loglevel = 2
[02:06:47.828] remote.SSH.enableDynamicForwarding = true
[02:06:47.829] remote.SSH.enableRemoteCommand = false
[02:06:47.829] remote.SSH.serverPickPortsFromRange = {}
[02:06:47.829] remote.SSH.serverInstallPath = {}
[02:06:47.829] remote.SSH.permitPtyAllocation = false
[02:06:47.829] remote.SSH.preferredLocalPortRange = undefined
[02:06:47.829] remote.SSH.useCurlAndWgetConfigurationFiles = false
[02:06:47.829] remote.SSH.experimental.chat = true
[02:06:47.829] remote.SSH.experimental.enhancedSessionLogs = true
[02:06:47.829] remote.SSH.httpProxy = {"*":""}
[02:06:47.829] remote.SSH.httpsProxy = {"*":""}
[02:06:47.837] VS Code version: 1.105.1
[02:06:47.837] Remote-SSH version: remote-ssh@0.120.0
[02:06:47.837] win32 x64
[02:06:47.843] SSH Resolver called for host: ark-kun-dev-mode-python@ssh.hf.space
[02:06:47.843] Setting up SSH remote "ssh.hf.space"
[02:06:47.855] Using commit id "7d842fb85a0275a4a8e4d7e040d2625abbf7f084" and quality "stable" for server
[02:06:47.855] Extensions to install: 
[02:06:47.859] Install and start server if needed

[02:06:52.342] Checking ssh with "C:\WINDOWS\System32\OpenSSH\ssh.exe -V"
[02:06:52.371] > OpenSSH_for_Windows_9.5p1, LibreSSL 3.8.2

[02:06:52.376] Running script with connection command: "C:\WINDOWS\System32\OpenSSH\ssh.exe" -T -D 62954 "ark-kun-dev-mode-python@ssh.hf.space" sh
[02:06:52.378] Generated SSH command: 'type "C:\Users\Ark\AppData\Local\Temp\vscode-linux-multi-line-command-ssh.hf.space-746041419.sh" | "C:\WINDOWS\System32\OpenSSH\ssh.exe" -T -D 62954 "ark-kun-dev-mode-python@ssh.hf.space" sh'
[02:06:52.379] Using connect timeout of 17 seconds
[02:06:52.380] Terminal shell path: C:\WINDOWS\System32\cmd.exe
[02:06:52.610] > 
[02:06:52.611] Got some output, clearing connection timeout

Expected Behavior

I need to connect to HuggingFace Space dev mode. https://huggingface.co/docs/hub/spaces-dev-mode

Actual Behavior

I need to connect to HuggingFace Space dev mode.

Normal SSH connection works:

"C:\WINDOWS\System32\OpenSSH\ssh.exe" "ark-kun-dev-mode-python@ssh.hf.space" ls
Dockerfile
README.md
__pycache__
app2.py
requirements.txt

But the generated command produces no output:

type "C:\Users\Ark\AppData\Local\Temp\vscode-linux-multi-line-command-ssh.hf.space-746041419.sh" | "C:\WINDOWS\System32\OpenSSH\ssh.exe" -T -D 62954 "ark-kun-dev-mode-python@ssh.hf.space" sh

type "C:\Users\Ark\AppData\Local\Temp\vscode-linux-multi-line-command-ssh.hf.space-746041419.sh" | "C:\WINDOWS\System32\OpenSSH\ssh.exe" -T -D 62954 "ark-kun-dev-mode-python@ssh.hf.space"

type "C:\Users\Ark\AppData\Local\Temp\vscode-linux-multi-line-command-ssh.hf.space-746041419.sh" | "C:\WINDOWS\System32\OpenSSH\ssh.exe" -T "ark-kun-dev-mode-python@ssh.hf.space" sh

type "C:\Users\Ark\AppData\Local\Temp\vscode-linux-multi-line-command-ssh.hf.space-746041419.sh" | "C:\WINDOWS\System32\OpenSSH\ssh.exe" -T "ark-kun-dev-mode-python@ssh.hf.space"

Tried transferring the script to the remote host manually and running it. Got this:

34834b1a3683: running
Script executing under PID: 168346
Found existing installation at /home/user/.vscode-server...
Starting VS Code CLI...
Removing old logfile at /home/user/.vscode-server/.cli.7d842fb85a0275a4a8e4d7e040d2625abbf7f084.log
Spawned remote CLI: 168364
Waiting for server log...
34834b1a3683: start
listeningOn==127.0.0.1:35469==
osReleaseId==debian==
arch==x86_64==
vscodeArch==x64==
bitness==64==
tmpDir==/tmp==
platform==linux==
unpackResult====
didLocalDownload==0==
downloadTime====
installTime====
serverStartTime==41==
execServerToken==9d6853a9-06b0-xxxxxx==
platformDownloadPath==cli-alpine-x64==
SSH_AUTH_SOCK====
DISPLAY====
34834b1a3683: end

Steps To Reproduce

1. Set up SSH keys with HuggingFace
2. Duplicate the official HF Space for dev mode testing: https://huggingface.co/spaces/dev-mode-explorers/dev-mode-python
3. Enable Dev mode on the Space
4. Try to connect to the Space via VSCode

Anything else?

The remote.SSH.useLocalServer setting intentionally does not having any effect on Windows.

I'm not very familiar with how SSH treats pipes and STDIN, but the following command is not producing any output:

echo "AAA" | "C:\WINDOWS\System32\OpenSSH\ssh.exe" -T "ark-kun-dev-mode-python@ssh.hf.space" "cat /dev/stdin"

Could it be that the STDIN is not piped all the way to the correct program?

Start with the generated command and temporary script shown in the Remote-SSH log, then compare it with the manually working SSH command and the manually transferred script output. Investigate how the Windows OpenSSH pipe, stdin, and -T -D options interact with the HuggingFace Spaces dev-mode endpoint; done means the documented reproduction connects successfully through VS Code.