RequestTTY does not modify the -T flag

[vincent-van-hoef]

The default ssh command from the extension seems to be fixed to ssh -T .... Changing the RequestTTY options in the ssh config file to one of "yes", "no", "auto" or "force" does not change the flag (I'm under the impression it should; might be wrong here).

As a consequence I get a Pseudo-terminal will not be allocated because stdin is not a terminal. error. Running the ssh command manually with the -t flag does connect me to the server.

Seems to be referenced before here: #5683

Thanks!

[tanhakabir]

To clarify:

Running the ssh command manually with the -t flag does connect me to the server.

This means if you use terminal or PowerShell, you're able to connect to the remote with a -t flag but not -T?

[vincent-van-hoef]

Sorry, that was a bit unclear. Indeed, connecting from a terminal to the remote server with -t works, while -T results in the same error about the pseudo terminal.

[tanhakabir]

Sorry I realize I had forgotten to reply here.

With -T we're preventing the remote from allocating pseudo terminals. We need to do this to ensure that the VS Code server is set up properly on the remote.

With -t you're actually requesting for the remote to use a pseudo terminal. Does your server then need pseudo terminals to successfully connect and interact with them? What happens if you don't set -T nor -t?

[heroboy]

I have same issue. I can't connect with '-T'.
Here is the output

[14:34:35.259] Log Level: 1
[14:34:35.262] remote-ssh@0.70.0
[14:34:35.262] win32 x64
[14:34:35.263] SSH Resolver called for "ssh-remote+20.0.0.229", attempt 1
[14:34:35.264] "remote.SSH.useLocalServer": false
[14:34:35.267] "remote.SSH.showLoginTerminal": true
[14:34:35.268] "remote.SSH.remotePlatform": {}
[14:34:35.268] "remote.SSH.path": undefined
[14:34:35.268] "remote.SSH.configFile": undefined
[14:34:35.268] "remote.SSH.useFlock": true
[14:34:35.269] "remote.SSH.lockfilesInTmp": false
[14:34:35.269] "remote.SSH.localServerDownload": auto
[14:34:35.269] "remote.SSH.remoteServerListenOnSocket": false
[14:34:35.270] "remote.SSH.showLoginTerminal": true
[14:34:35.270] "remote.SSH.defaultExtensions": []
[14:34:35.270] "remote.SSH.loglevel": 1
[14:34:35.271] "remote.SSH.serverPickPortsFromRange": {}
[14:34:35.271] "remote.SSH.enableDynamicForwarding": true
[14:34:35.271] "remote.SSH.serverInstallPath": {}
[14:34:35.272] SSH Resolver called for host: 20.0.0.229
[14:34:35.272] Setting up SSH remote "20.0.0.229"
[14:34:35.311] Using commit id "d6ee99e4c045a6716e5c653d7da8e9ae6f5a8b03" and quality "stable" for server
[14:34:35.315] Install and start server if needed
[14:34:36.840] Checking ssh with "ssh -V"
[14:34:36.876] > OpenSSH_for_Window
[14:34:36.876] > s_8.1p1, LibreSSL 3.0.2

[14:34:36.880] Remote command length: 6110/8192 characters
[14:34:36.880] Running script with connection command: ssh -T -D 57648 "20.0.0.229" powershell
[14:34:36.883] Terminal shell path: C:\WINDOWS\System32\cmd.exe
[14:34:37.319] "install" terminal received data: "�[2J�[m�[H�]0;C:\WINDOWS\System32\cmd.exe��[?25h"
[14:34:37.319] Got some output, clearing connection timeout
[14:34:37.342] "install" terminal received data: "�[25l�[K
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�[K
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�[K�[H�[?25h"

And here is what happened when connect in the command line:

C:\Users\heroboy\.ssh>ssh -T 20.0.0.229
WHrCg@b g

[pedroilidio]

I have the same issue here. My use case is that I want to be able to automatically attach to a screen after connecting to the host, which I could perfectly achieve outside vscode with the settings:

Host myhost
    HostName <myhost>
    User <myuser>
    RequestTTY force
    RemoteCommand screen -Dr vscode

So that ssh myhost works, while ssh -T myhost does not.

[maxencefaldor]

I have the same issue here, I would like to use tmux with the following ssh config file:

Host host
HostName
User
RemoteCommand tmux new-session -As project
RequestTTY force

but VSCode connects using: ssh -v -T -D 52289 -o ConnectTimeout=15 host
instead of using -t flag, resulting in an error.

How can I change the behavior of VSCode to connect using : ssh -v -t -D 52289 -o ConnectTimeout=15 host
which works?

[SouthOfAsia]

I am experiencing the same issue. I want to use VSCode to connect to my server,which system is Windows Server 2012.
When I use ssh -T Administrator@xxx.xxx.xx.xx, the shell returns WHrCg@b g.
However, when I use ssh Administrator@xxx.xxx.xx.xx, it returns the correct output. I believe that the -T option might have confused me.

[SouthOfAsia]

I am experiencing the same issue. I want to use VSCode to connect to my server,which system is Windows Server 2012. When I use ssh -T Administrator@xxx.xxx.xx.xx, the shell returns WHrCg@b g. However, when I use ssh Administrator@xxx.xxx.xx.xx, it returns the correct output. I believe that the -T option might have confused me.

Is not ‘-t’ makes error
I update my Server‘s Powershell Version 4.0 to 5.0 and it works.

[adamfitz]

I am experiencing the same issue, where I am not able to open a remote ssh session to my target server (linux) because vscode is forcing the use of the -T flag.

I tested the following connection string from my client and confirmed I get the same connection error as I get when testing from vscode:

"C:\windows\System32\OpenSSH\ssh.exe" -T -D 61757 "$target_server"

When I remove the -T flag the connection works as expected.

Also I can see the ssh config parameters RemoteCommand and RequestTTY are simply ignored by vscode so I am unable to use this as a workaround.

Is there any option/setting to allow the user to change this behavior and remove the -T flag from the connection string or force a TTY as a workaround?

[paperclover]

haven't verified but a potential way to reproduce this may be to install debian 12.2 and switch your user's shell to fish, ssh -T no longer works on that user.

is there a reason we cannot make -T vs -t configurable, and also detect a hang to make this error easier for users to deal with.

[jcarpinelli-bdai]

I see RemoteCommand is experimentally supported. That's great! I hope it is possible to add RequestTTY support as well. Some shells, like nushell, require TTY. Right now, to use non-standard shells like nushell, I believe users can also disable the "Use Local Server" option of the Remote SSH extension; that seems to cause VSCode to request a TTY for each terminal.

[YourGraceQI]

I am facing the same issue, while vs remote ssh keep adding the -T flag, adding RequestTTY doesn't help, and RemoteCommand also do nothing, anyone can help?

[iamsiita]

vscode keeps adding -T flag even after adding RequestTTY force.
vscode continues to add -T flag even if the "Use Local Server" option is turned off.
Is there a way to disable the -T flag? If not, will it be added in the future?

[ManiaciaChao]

Same here. My case is to connect to a server which is bebind a jump server, with option ProxyJump
ssh hostname works but not for ssh -T hostname.

However I don't think this is an issue because there's option to turn off this behavior:

  "remote.SSH.permitPtyAllocation": true

[roblourens]

I think this issue is a dupe of #7558 (comment) that I didn't realize we had. Yes, that new setting is right, please try it out and give feedback in the other issue, thanks