Jsch error - failed to send channel request

问题:

I am trying to connect to a SFTP remote server using JSCH library version 0.1.49. Every time I run the program I receive the following error :

Initializing... Connection to SFTP server is successfully com.jcraft.jsch.JSchException: Unable to connect to SFTP server.com.jcraft.jsch.JSchException: failed to send channel request at shell.MainClass.JschConnect(MainClass.java:95) at shell.MainClass.main(MainClass.java:30) 

line 30 is : sftpChannel.connect() from the code below :

    System.out.println("Initializing...");     JSch jsch = new JSch();      Session session = null;     try {            session = jsch.getSession(ProjectConstants.rmUsername,ProjectConstants.rmHost, 22);         session.setPassword(ProjectConstants.rmPassword);          java.util.Properties config = new java.util.Properties();          config.put("StrictHostKeyChecking", "no");         session.setConfig(config);          session.connect();         if (session.isConnected() == true) {             System.out.println("Connection to SFTP server is successfully");         }          ChannelSftp sftpChannel = (ChannelSftp) session.openChannel("sftp");         try {             sftpChannel.connect();         } catch (Exception e) {             throw new JSchException("Unable to connect to SFTP server. "                     + e.toString());         } 

the credentials I am using are correct ( it connects through FileZilla using the same data ), and I also disabled the proxy for that server ( either way I get the same error with or without proxy )

If anyone could help me I would greatly appreciate it as I am stuck with this error for about a week now ...

Thank you.

回答1:

Check if SFTP server is started and running.

I had encountered the same issue - I was not able to open SFTP channel to my server, but I could connect with WinSCP. It took me some time to notice that WinSCP would fallback to SCP hence confusing me. Starting the server solved this issue.

回答2:

In /etc/ssh/sshd_config I changed:

Subsystem sftp /usr/lib/openssh/sftp-server  

to:

Subsystem sftp internal-sftp  

It helps.

回答3:

Check Subsystem sftp /usr/lib/openssh/sftp-server in /etc/ssh/sshd_config

文章来源: Jsch error - failed to send channel request