Introduction

This document describes the functionality of the JobSchedulerSSHJob and the parameters to configure the Job properly. Additionaly this document provides a minimal example for a SSH Job configuration.

Mode Of Operation

Unix based operating systems provide a SSH client, while MS Windows operating systems do not. 

With the JobSchedulerSSHJob you can execute shell commands and scripts on a remote host, running a SSH server, without the need to install a local SSH client. 

For a minimal SSH job only a limited amount of parameters has to be configured as shown in the example below.

Example

A minimal SSH Job configuration

<?xml version="1.0" encoding="ISO-8859-1"?>
<job title="Launch remote commands or executable files by SSH" stop_on_error="no">
    <description >
        <include  file="jobs/JobSchedulerSSHJob.xml"/>
    </description>
    <params >
        <param  name="host" value="HOSTNAME"/>
        <param  name="port" value="22"/>
        <param  name="user" value="USERNAME"/>
        <param  name="password" value="PASSWORD"/>
        <param  name="auth_method" value="password"/>
        <param  name="command" value="printenv"/>
    </params>
    <script  language="java" java_class="sos.scheduler.job.SOSSSHJob2JSAdapter"/>
    <run_time />
</job>

Parameters

There are three types of parameters:

• Required Parameters
  • Parameters which are required to run the Job
    • Example: To connect to a remote host, the  'host' parameter is always required to run the Job properly.
• Conditional Parameters
  • Parameters which depend on other parameters
    • Example: Depending on the value of the 'auth_method' parameter ('password' or 'publickey') one of the conditional parameters, the 'password' parameter or the 'publickey' parameter, has to be set.
• Additional Parameters
  • Parameters which are not required, but depend on specific conditions
    • Example: To connect with a remote host only a 'host' parameter is required. If the connection has to be instantiated over a proxy, the additional parameter 'proxy_host' is required.

Required Parameters

host

• default value:
  
  • empty
• description:
  • This parameter specifies the hostname or IP address of the SSH server to which a connection is to be made.

port

• default value:
  • 22
• description:
  •  This parameter specifies the port number of the SSH server.

user

• default value:
  • empty
• description:
  • This parameter specifies the user account to be used when connecting to the SSH server.

command_delimiter

• default value:
  • %%
• description:
  • Command delimiter characters are specified using this parameter. These delimiters can then used in the command parameter to seperate multiple commands. These commands are then excecuted in a separate SSH session.

Conditional Parameters

auth_method

• default value:
  • publickey
• description:
  • This parameter specifies the authorization method for the SSH server - the publickey and password methods are supported. When the publickey authorization method is used, then the path name of the private key file must be set in the auth_file parameter. Should the private key file be secured by a password then this must be specified with the password parameter. For the password authorization method the password for each user account must be specified using the password parameter. The authorization methods which are enabled depend on the SSH server configuration. Not all SSH server configurations support the password authorization method.

password

• default value:
  • empty
• description:
  • This parameter specifies the user account password for authorization by the SSH server and must be specified if the password authorization method is specified in the auth_method parameter. 
    Alternatively, this parameter may specify the secret key passphrase if the publickey authorization method has been set in the auth_method parameter.

 auth_file

• default value:
  • empty
• description:
  • This parameter specifies the path and name of a user's private key file used for registeration on an SSH server. This parameter must be specified if the publickey authorization method has been specified in the auth_method parameter. 
    If the private key file is secured with a passphrase, the password parameter hat to be set with the passphrase.

command

• default value:
  • emplty
• description:
  • This parameter specifies a command that is to be executed on the SSH server. Multiple commands can be separated by the command delimiter that is specified using the command_delimiter parameter.

command_script

• default value:
  • empty
• description:
  • This parameter can be used as an alternative to command, command_delimiter and command_script_file. It contains scriptcode which will be saved to a temporary (script-)file on the remote host and executed there. The script can access task and order parameters by environment variables. The names are in upper case and have "SCHEDULER_PARAM_" as a prefix. Order parameters with the same name overwrite task parameters.

command_script_file

• default value:
  • empty
• description:
  • This parameter can be used as an alternative to command, command_delimiter and command_script. It contains the name of a local (script-)file, which will be transferred to the remote host and executed there. The script can access task and order parameters by environment variables. The names are in upper case and have "SCHEDULER_PARAM_" as a prefix. Order parameters with the same name overwrite task parameters.

Additional Parameters

proxy_host

• default value:
  • empty
• description
  • The value of this parameter is the host name or the IP address of a proxy used to create the connection to the SSH server. The use of a proxy is optional.

proxy_port