How to Troubleshoot NetSuite SFTP Connection Issues

1. Distinguish SFTP from FTPS

   Ensure the connection is using SFTP (SSH File Transfer Protocol), as NetSuite's N/sftp module exclusively supports SFTP, not FTPS (FTP over SSL).

2. Verify Host Key

   An invalid host key can prevent a successful connection. The host key is sent in sftp.createConnection(options). To verify the host key, use Windows Powershell with the following command, replacing alghorithmtype and hosturl with your specific details:

ssh-keyscan -t alghorithmtype hosturl

For example:

ssh-keyscan -t rsa packsize.nearlynatural.com

1. Validate Username and Password

   Incorrect credentials are a common cause of failure. Verify the username and password by attempting to log in to the SFTP server using a client like FileZilla.

2. Review SFTP Server Criteria

   Refer to SuiteAnswer 61290 for detailed criteria that the SFTP server must meet for successful integration with NetSuite.

3. Check Authentication Method Compatibility

   In a specific customer's case, their SFTP server was configured for password and key authentication. At that time, this configuration was incompatible with the N/sftp module's then-understood capabilities, which primarily supported username/password. Adjusting the server's authentication setting to use password only resolved the issue for that client.

   It is important to note that NetSuite's N/sftp module now supports more robust authentication methods, including username/password, two-factor authentication (password and key combination), and SSH key-based authentication. Ensure your SFTP server's authentication method aligns with one of these supported options.