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shellunixsftpjsch

How to upload the file to another SFTP server from shell channel by using Jsch?

Step 1: Session connect

....
session.connect()

Step 2: Shell channel

channel = session.openChannel("shell");

Step 3: Execute ssh commands to login Unix server and go to the required path cd /logs/server

PrintStream shellStream = new PrintStream(channel.getOutputStream());  // printStream for convenience 
channel.connect(); 
shellStream.println(command); 
shellStream.flush();

step 4: Get the file from Unix server and put into SFTP:

code to connect sftp channel and put the file from unix server to sftp.

So I want to upload the file (logs/server/server.log) from Unix server (which I logged in using shell channel) to SFTP server.

Both source and destination are remote.

Is it possible to do by using JSch?

Solution

  • An SFTP protocol (let alone JSch SFTP library) has no support for transfers between two remote servers.

    If you have a shell access to one of the servers, you can try to transfer the files by using a command-line (OpenSSH) sftp client on the server. It's doable. Problematic is an authentication part, as it's non-interactive session. You would have to use an unencrypted private key, an agent forwarding or sshpass.

    Obvious and simple implementation is to download the files from the "Unix" server to a local machine and then upload them to the "SFTP" server. But you need to use the SFTP channel, not the shell channel, for the download.