Typescript: ssh2-sftp-client trouble connecting to sftp server while FileZilla can

Question

I have searched stackoverflow and google extensivly and not found a solution yet.

Using Typescript, node v16.18.0 and ssh2-sftp-client, the code below can successfully connects to my sftp server (hosted on IIS) which requires a username, password and a private key.

let sftp = new Client();
// sftp.tryKeyboard = true;
let conn = await sftp
    .connect({
        protocal: 'sftp',
        host: '##.##.##.##',
        port: 22,
        username: 'someUserName',
        remotePath: 'somePaht',
        password: 'somePassword',
        privateKey: key,
        // tryKeyboard: true,   
    })
    .then(async() => {
        // return;
        console.log('You connected!');
    })
    .catch((err: any) => {
        console.log(err, 'catch error');
    });

However, using the exact same code but passing in connection parameters for a different sftp server (hosted on Linux) that requires a username and privatekey, but not a password fails to connect.

let sftp = new Client();
// sftp.tryKeyboard = true;
let conn = await sftp
    .connect({
        protocal: 'sftp',
        host: '##.##.##.##',
        port: 22,
        username: 'gp',
        remotePath: 'gp',
        //password: 'NA',
        privateKey: key,
        // tryKeyboard: true,   
    })
    .then(async() => {
        // return;
        console.log('You connected!');
    })
    .catch((err: any) => {
        console.log(err, 'catch error');
    });

and this is the error I get using the above code:

Error: connect: getConnection: All configured authentication methods failed at SftpClient.fmtError (D:\app\node_modules\ssh2-sftp-client\src\index.js:111:22) at SftpClient.connect (D:\app\node_modules\ssh2-sftp-client\src\index.js:249:37) at processTicksAndRejections (node:internal/process/task_queues:96:5) at async getSftpConnection (D:\app\index.ts:67:12) { code: 'ERR_GENERIC_CLIENT', custom: true } catch error

As a test I used the exact same values to connect using the FileZilla ftp client and it connects with no problem. I don’t have admin access to the Linux server so I can’t get additional information about its configuration, but I can confirm that these connection parameter values work in FileZilla. Obviously FileZilla is doing something I am not.

This is the basic configuration in FileZilla:

and the folder it connected to:

How can I troubleshoot this? How can I get additional information about what’s causing the connection to fail?

Thank you.

Answer 1

It turns out that the type of key I was using was a rsa. IIS is much more forgiving then Linux. To make this work on the Linux sftp I had to add these 2 lines in the config file

hostkeyalgorithms=ssh-rsa,[email protected]
pubkeyacceptedalgorithms=+ssh-rsa,[email protected]

the config file is located at:

/etc/ssh/sshd_config

However, in this screenshot you can see that the 2 lines are commented out. Thats because after I got this to work, I commented them and tried using a key in the ED25519 format which did work.

Summary, I should have used a ED25519 type of key so I would not have needed to mess with the Linux server. But if I want to the rsa key, then add the 2 lines above to the config file.