Ant SshExec task throwing JschException : Auth fail

[Sonny Gill]

Hi guys,

This script was working fine, but stopped working after the remote server was upgraded from Suse 9 to Suse9.1 .
The problem should not be the ssh hosts file, because I can use ssh directly to connect without a problem, and also if I remove that file, ant throws a different exception (something along the lines of Host lookup failed).
I am really stumped that why the authorization is failing when the password is included right there in the script (I know that is not very secure, this is to get it working)

Any help is greatly appreciated!


Following is the stripped down ant script -

  
<?xml version="1.0"?>
<project name="sshdebug" default="default" basedir=".">
    <target name="default" >
        <sshexec host="192.168.1.1"
            username="root"
            trust="yes"
            password="rootpassword"
            command="ls"/>
</target>
</project>

And the exception thrown is -

default:
  [sshexec] Connecting to 192.168.2.2:22
 
BUILD FAILED
/home/sandeep/sshdebug.xml:9: com.jcraft.jsch.JSchException: Auth fail
        at org.apache.tools.ant.taskdefs.optional.ssh.SSHExec.execute(SSHExec.java:211)
        at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:275)
        at org.apache.tools.ant.Task.perform(Task.java:364)
        at org.apache.tools.ant.Target.execute(Target.java:341)
        at org.apache.tools.ant.Target.performTasks(Target.java:369)
        at org.apache.tools.ant.Project.executeTarget(Project.java:1214)
        at org.apache.tools.ant.Project.executeTargets(Project.java:1062)
        at org.apache.tools.ant.Main.runBuild(Main.java:673)
        at org.apache.tools.ant.Main.startAnt(Main.java:188)
        at org.apache.tools.ant.launch.Launcher.run(Launcher.java:196)
        at org.apache.tools.ant.launch.Launcher.main(Launcher.java:55)
Caused by: com.jcraft.jsch.JSchException: Auth fail
        at com.jcraft.jsch.Session.connect(Unknown Source)
        at com.jcraft.jsch.Session.connect(Unknown Source)
        at org.apache.tools.ant.taskdefs.optional.ssh.SSHBase.openSession(SSHBase.java:180)
        at org.apache.tools.ant.taskdefs.optional.ssh.SSHExec.execute(SSHExec.java:143)
        ... 10 more
--- Nested Exception ---
com.jcraft.jsch.JSchException: Auth fail
        at com.jcraft.jsch.Session.connect(Unknown Source)
        at com.jcraft.jsch.Session.connect(Unknown Source)
        at org.apache.tools.ant.taskdefs.optional.ssh.SSHBase.openSession(SSHBase.java:180)
        at org.apache.tools.ant.taskdefs.optional.ssh.SSHExec.execute(SSHExec.java:143)
        at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:275)
        at org.apache.tools.ant.Task.perform(Task.java:364)
        at org.apache.tools.ant.Target.execute(Target.java:341)
        at org.apache.tools.ant.Target.performTasks(Target.java:369)
        at org.apache.tools.ant.Project.executeTarget(Project.java:1214)
        at org.apache.tools.ant.Project.executeTargets(Project.java:1062)
        at org.apache.tools.ant.Main.runBuild(Main.java:673)
        at org.apache.tools.ant.Main.startAnt(Main.java:188)
        at org.apache.tools.ant.launch.Launcher.run(Launcher.java:196)
        at org.apache.tools.ant.launch.Launcher.main(Launcher.java:55)
 

[Sonny Gill]

So...I happened to find out why this was happening.
The reason the script started to fail must have been a configuration change on the remote system.

Ref - http://sancho-gui.sourceforge.net/faq.phtml

SSH2 NOTE: (might not be required if using 0.9.4-22 or newer and id_dsa)

In order for SSH2 tunneling to function correctly one must ensure that the
following line is uncommented in /etc/ssh/sshd_config :
--------------------------CUT-------------------------------
# Change to yes to enable tunnelled clear text passwords
PasswordAuthentication yes
--------------------------CUT-------------------------------

Otherwise the initiation of the tunnel will fail with
"SSH Initialization failed, try again?
com.jcraft.jsch.JSchException: Auth fail"

Thanks to whoever posted the above faq entry

After editing my remote sshd configuration, I can run the script again.

A discussion of what this setting means can be found here -
http://www.lugod.org/mailinglists/archives/vox-tech/2005-07/msg00012.html

Sonny

[Ananya Joisa]

Hi,

I had also got the error "com.jcraft.jsch.JSchException: Auth fail " while using the ANT task sshexec and I followed the solution given in this forum.

# Change to yes to enable tunnelled clear text passwords
PasswordAuthentication yes

But I still see the same error. Could anyone help?

[Peter Johnson]

There is more to ssh authentication than simply setting a property. If the remote system uses public/private keys, then how to set that up on your system is much different than if the remote system uses a username/password scheme. So before we can help you, we need to know what kind of authentication is used by the remote system for ssh.