Troubleshooting SFTP Connections

If you are having difficulty connecting to your SFTP server:

  1. Verify that the server you are connecting to supports SFTP connections.

Note:

Deva xFTP supports SFTP, a secure service provided by the SSH2 host in which the server both encrypts the data and handles the file transfer. This should not be confused with FTP over SSH2, in which SSH2 uses port forwarding capabilities to forward standard FTP transactions through an encrypted tunnel but the actual file is transferred by a separate, non-secure FTP server. If you are unsure if the host is supporting SFTP, check the connection port. SFTP usually occurs over port 22.

  1. Try toggling the compression options in the SSH2 Security page.

  2. Verify the authentication mechanism supported and required by the server. It may require password, public key (identity file), Host Based or all the three (see Important note below).

  3. If public key authentication is required, be sure to provide a copy of the public key you created to the server’s administrator, as it must be in the server’s trusted list in order for you to connect.

  4. If the server administrator created a public key for you, be sure to replace your existing one with it and select the provided key from within the SSH2 Security page.

  5. Copy the connection log to a text file or e-mail to assist in troubleshooting when contacting your FTP or Web service provider or the Deva xFTP support team.

Configuration Notes

To use public key authentication, you must send your public key to the server administrator before making an SSH2 connection. If the server is running OpenSSH, convert the public key:

  1. Create an identity file in the client.

  2. Send the public key (Identity.pub) to the server administrator (via FTP, e-mail, etc.)

  3. The server administrator must convert the public key to OpenSSH, check it with wordcount, and add it to authorized_keys.

 

Command sequence:

ssh-keygen -i -f Identity.pub > sshpub

wc sshpub

cat sshpub > ~\.ssh\authorized_keys

 

Note:

Wordcount should return a "1" as the first number. OpenSSH asks for the identity files password the first time you log in. If Deva xFTP Professional fails to connect, contact our support team and provide the kernel version, OpenSSH build, and the Deva xFTP Professional build number (located under Help > About).