SFTP SSH connector BadGateway

[dani135]

Hi Power Automate community!

I get this error when trying to connect to an S3 bucket. All the credentials are correct, and I am able to connect using terminal. But Power Automate doesn't want to connect. I checked with my company's network department, and they confirmed that the Firewall is not blocking this connection. Could you please advise?

[lbendlin]

Did you declare your connection on your gateway?  As far as Power Automate is concerned, S3 counts as "on premise"  if it is not in the Azure cloud.

[dani135 · Accepted solution]

Found the solution:

1. The private key needs to be in this format:

-----BEGIN RSA PRIVATE KEY-----

NOT 

-----BEGIN OPEN SSH PRIVATE KEY-----

2. And you need to specify the root folder: /bucketname/folder/ when making the SFTP SSH connection in PA flow.

[ngrdy07]

Hello,

I am running into Bad Gateway error. But I'm disabling the SSH host key validation and authenticating with username and password. Can you please advise ?

Thanks

[dani135]

Hello,

Could you share a screenshot of your current setup with sensitive info greyed out? What service are you trying to connect to (S3)?

[YazeedAblan]

Hello, any solution for this one ?

[JohnMo11]

This blog describes how to see the error behind the BadGateway shown. Basically:

1. open DEV tools (F12) in the browser.
2. navigate to Network
3. click the "Folder" request in the left pane
4. click Preview and look for inner error

Mine says
"An existing connection was forcibly closed by the remote host"

This is probably due to Power Automate creating simultaneous connections to the server. I've not been able to find out how to solve this. Connection with WinSCP is working without problems.

[lbendlin]

Can you set the parallelism for that action to 1?

[Valcoren]

I have been running into the same issue with connecting to SFTP with a cloud triggers. Its random when it happens forcing a retrigger until it pushes through. I've broken up all parallels to down to a single action still and still experience random connection issues. 

[collinnunis]

Hi there, I am also trying to do the same thing - connecting to an S3 bucket using Power Automate. Can I confirm that you needed to whitelist the IP addresses of Power Automate (https://learn.microsoft.com/en-us/connectors/common/outbound-ip-addresses#power-platform) in the firewall to allow this to happen? 

[dani135 · Accepted solution]

I don't think I whitelisted those IP addresses before doing this. But anyone who is still struggling with this SFTP SSH connector, please try these steps:

1. The connection name can be anything but try to name it something that you will immediately recognize, especially if you plan to have multiple SFTP SSH connections in the future.

2. The host server address is the URL of your server that you set up using the Transfer Family. Please refer to these tutorials: https://www.youtube.com/watch?v=3_HHSnoFsoM, https://docs.aws.amazon.com/transfer/latest/userguide/getting-started.html 

3. The ‘User name’ is the name that you created during the previous step when you set up your server.

4. Leave the password field empty.

5. The SSH private key is a key that you can generate from your computer’s terminal using this command - ssh-keygen -m PEM -t rsa -b 4096 -f name-of-the-key. Please keep in mind that you can find your keys in this directory: ‘C:\Users\<your username>’. The public key will have the ‘.pub’ extension and the private key will not have any extension. But you can open both using a text editor of your choice. Copy the contents of the private key into the ‘SSH private key’ field and copy the contents of the open key into your server. It’s essential that both keys are in place before you establish your SFTP - SSH connection.

6. If you had generated a passphrase during the previous step, enter it in the ‘SSH private key passphrase’ field.

7. Enter port number 22.

8. Disable the SSH host key validation.

9. Leave SSH host key finger-print empty.

10. In the ‘Root folder path,’ enter your bucket name like this: ‘/your_bucket_name/folder/'

11. Click ‘Create.' If you encounter an error, check that your RSA private key is correct (it must start with ‘BEGIN RSA PRIVATE KEY’) and that your root folder path contains a forward slash before the bucket name. If you still can’t connect, check that you spelled the host server address correctly and that your user has sufficient permissions to access and read from the bucket.

[naidu1811]

kudos  @dani135 ,Its working for me.

1. The connection name can be anything but try to name it something that you will immediately recognize, especially if you plan to have multiple SFTP SSH connections in the future.

2. The host server address is the URL of your server that you set up using the Transfer Family. Please refer to these tutorials: https://www.youtube.com/watch?v=3_HHSnoFsoM, https://docs.aws.amazon.com/transfer/latest/userguide/getting-started.html 

3. The ‘User name’ is the name that you created during the previous step when you set up your server.

4. Leave the password field empty.

5. The SSH private key is a key that you can generate from your computer’s terminal using this command - ssh-keygen -m PEM -t rsa -b 4096 -f name-of-the-key. Please keep in mind that you can find your keys in this directory: ‘C:\Users\<your username>’. The public key will have the ‘.pub’ extension and the private key will not have any extension. But you can open both using a text editor of your choice. Copy the contents of the private key into the ‘SSH private key’ field and copy the contents of the open key into your server. It’s essential that both keys are in place before you establish your SFTP - SSH connection.

6. If you had generated a passphrase during the previous step, enter it in the ‘SSH private key passphrase’ field.

7. Enter port number 22.

8. Disable the SSH host key validation.

9. Leave SSH host key finger-print empty.

10. In the ‘Root folder path,’ enter your bucket name like this: ‘/your_bucket_name/folder/'

11. Click ‘Create.' If you encounter an error, check that your RSA private key is correct (it must start with ‘BEGIN RSA PRIVATE KEY’) and that your root folder path contains a forward slash before the bucket name. If you still can’t connect, check that you spelled the host server address correctly and that your user has sufficient permissions to access and read from the bucket.

[collinnunis]

Thanks! I followed these tips after getting the network admin to whitelist the public IP addresses. This solved my issues.