Chapter 5 Script Repository and Script Launcher Modules

The Script Repository and Script Launcher modules included with System Reliability Manager enable you to execute scripts that perform arbitrary management tasks on remote devices. The ability to execute scripts on remote devices reduces the processing load on a central management station. This ability also provides a mechanism to keep polling local.

This chapter covers the following topics:

• Script Repository Module

• Script Launcher Module

Script Repository Module

The Script Repository module enables you to view the scripts available on the agent machine to be run by the Script Launcher module. The Script Repository module also lists the languages supported by the Script Launcher module.

(On Solaris 10) Dynamic Tracing (DTrace) allows the user to observe the behavior of user programs and operating system. DTrace allows the user to explore a system, to understand how it works, track down performance problems across layers of software, or locate the cause of aberrant behavior. D programming language is provided with Solaris 10 to write programs that can help in debugging a system.

For details on DTrace, see Solaris Dynamic Tracing Guide.

The Script Repository module contains commonly used DScripts for Solaris 10. You can run these scripts from the Script Launcher module.

The Script Information group includes two tables:

• The Language Table, which lists the supported languages. Currently, Java, shell script, and DScript (on Solaris 10) are included.

• The Script Table, which enables you to view available scripts on the agent

The security for Script Repository module is implemented as follows:

• Only the root user can place scripts in the following directory:

  /var/opt/SUNWsymon/SysMgmtPack/script-launcher/scripts

• Each script specifies the users and groups who are allowed to execute the script. These users and groups are specified as entries within Users and Groups in the script configuration file. Additionally, these fields can be modified from any console through the Scripts Table. Only esadm users are allowed to modify these fields.

• root cannot be in the Script Users field of the Script Table.

To Access the Script Repository Module

Steps

1. Load the module.

   For more information on loading and unloading modules, see the Sun Management Center 3.6 User’s Guide. The Script Repository module is available under Local Applications in the Navigator window.

2. In the Browser window, double-click Local Applications.

   The category expands.

3. Under Local Applications, double-click Script Repository.

   The category expands.

4. Double-click the Script Information folder to view the Language Table and the Script Table.

   

Language Table

The first table in the Script Information group is the Language Table. It lists all the scripting languages supported on the agent. Each table entry has the following attributes:

• Language Name. (For example, Java)

• Language Source. (For example, /usr/java)

There are no commands available for this table. You cannot specify a new language or remove a language. The number of entries is fixed and is defined by the implementation of the module and the languages it supports.

You can modify the Language Source by typing new information in the cell.

Alarms

System Reliability Manager generates an information (INFO) alarm if the language cannot be found at the specified location.

Script Table

The Script Table lists all scripts known to the Script Launcher on the agent.

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Note –

(On Solaris 10) Some pre-defined DScripts are added to the Script Table.

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Each entry in the table has the attributes listed in the following table.

Table 5–1 Script Table Values

Attribute	Description
Script Owner	The user on the agent who owns this script.
Script Name	The script name.
Description	A description of the purpose of the script.
Admin Status	The following statuses are possible:  Enabled indicates that the owner allows the script to be used by others. Disabled indicates that the owner does not allow the script to be used by anyone else.
Operation Status	The following statuses are possible:  Enabled indicates that the script is available and can be started by a launch table entry. Disabled indicates that the script cannot be used. NoSuchScript indicates that the script does not exist at the specified location. WrongLanguage indicates that the language is not known.
Language	The language in which the script is written. This value needs to be one of the languages listed in the Language Table.
Script Source	File name of the script.
Default Argument	The default argument for this script.
Users	The users who are permitted to use this script.
Groups	The UNIX groups that are permitted to use this script.

The fields you can modify through the browser are Admin Status, Script Users, and Groups. The Admin Status is the area where you enter the desired status of your script. For example, the Admin Status can be enabled or disabled. While this choice reflects your desired status, only the Operation Status reflects the actual status once the module determines that all criteria have been met and are ready.

Script Table Alarms

• An info alarm is issued if the script is not in a supported language.

• An info alarm is issued if the script is not accessible.

ScriptInfo.dat File

The ScriptInfo.dat contains information about the scripts that are available to be run. The addition of a new script to the ScriptInfo.dat file enables the module to recognize the script. All the scripts that belong to a user must be listed in this file.

The ScriptInfo.dat contains information about the scripts that are written in shell script, Java, and DScript (Solaris 10).

To Add a New Script

Steps

1. Write a new script.

   The format of the ScriptInfo.dat file follows the standard configuration file format.

   slice:attribute=value
   

2. Copy the new script to the ScriptInfo.dat file.

   The ScriptInfo.dat file is located in a directory identified by your user name, as in this example:

   /var/opt/SUNWsymon/SysMgmtPack/script-launcher/scripts/username/ScriptInfo.dat

   If this file already contains information about a script, add your script below the current information.

   The following example of the ScriptInfo.dat file contains two scripts.

   Script1:Owner = Scott
   Script1:Name = MyHello
   Script1:Desc = Says Hello
   Script1:Language = Java
   Script1:Source = Hello.class
   Script1:AdminStat = 1
   Script1:OperStat = 1
   Script1:Users = Noble
   Script1:Group = Staff
   Script2:Owner = Denise
   Script2:Name = MyFile
   Script2:Desc = Says Hello
   Script2:Language = Java
   Script2:Source = Hello.class
   Script2:AdminStat = 1
   Script2:OperStat = 1
   Script2:Users = Noble
   Script2:Group = Staff

Script Launcher Module

The Script Launcher module enables you to delegate management functions to agents. Management functions are management scripts written in a management scripting language. The Script Launcher module is a multi-instance module. All instances of the Script Launcher module access the same Script Repository module for language and script information.

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Note –

(On Solaris 10) You can run DScripts from the Script Launcher module.

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Caution –

Some DScripts may be monitoring continuously. The output of such scripts would be huge. It is recommended to avoid such scripts because they may slow down the CPU and may also hang the Java Console.

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The following code snippet can be attached to any DScript to control the flow of execution for a specific time period.

tick-1sec

/i++ >= 10/

{

exit(0);

}

In the above example, the DScript executes only for 10 seconds. The user can see the output after 10 seconds.

The module includes the following two tables:

• Launch Table – Describes scripts that are ready to be launched and indicates their parameters

• Result Table – Enables you to view the results of running a selected script

The Script Launcher module enables you to manipulate scripts as follows:

• Control who is allowed to read, write, and execute scripts from the Script Repository module

• Specify arguments for management scripts

• Initiate and terminate management scripts

• Monitor and control running management scripts

• View the results produced by running management scripts

• Control who is allowed to read, write, and execute scripts

The security for Script Launcher module is implemented as follows:

• root cannot be part of the LaunchOwner field of the Launch Table. To enable the root user of a machine to run scripts as a superuser, create a new user on the machine. Use that user name to run the scripts.

• The launchOwner must be a part of new esscrusers group on the server. Only esscrusers can create rows or make changes in the Launch Table.

• The Launch Owner, or launchOwner, must be a valid user on the agent machine. The user must be a local user or someone added through a service such as NIS on the agent. Scripts are run with the launch owner's permissions.

To Access the Script Launcher Module

Before You Begin

You must load the Script Repository Module before using the Script Launcher Module.

Steps

1. Load the module.

   See the Sun Management Center 3.6 User’s Guide for more information. The Script Repository module is available under Local Applications in the Browser window.

2. Double-click Local Applications in the Browser window.

3. Double-click Script Launcher.

   The Script Launcher displays the Launch Table and the Result Table.

   

Launch Table

The Launch Table controls the execution of all scripts. This table describes scripts that are ready to be launched along with descriptions of their parameters.

An entry in the Launch Table attaches an argument to a script. The entry also defines the owner, who is used to associate permissions to execute the script.

Several instances of a script may be created through one single entry on this table. Also, several entries on this table may point to a same script on the Script Table. You can execute several identical scripts with different arguments and different permissions. Scripts can only be run with the launch owner's permissions.

The Launch Table has the attributes listed in the following table.

Table 5–2 Launch Table Attributes

Attribute	Description
Launch Owner	The manager who owns this entry.
Launch Name	The name of the entry. Names should be unique for each row in the launch table.
Script Owner	In combination with the script name, identifies the script.
Script Name	In combination with the script owner, identifies the script.
Arguments	Arguments to be supplied to the script.
Launch Start	Initiates execution of a script. Before a script is launched, the following conditions must be satisfied:  The Operation Status for the entry should be in enabled state. There should be an entry in Script Table with the same values in the Script Owner and Script Name fields. The Script Operation Status field in the script table should be in enabled state. The Launch Owner has necessary security permissions to launch the script.
Launch Control	This object is used to request a state change for all running scripts in the Run Table started from the Launch Table.
Admin Status	The desired status of this launch table entry, which can be either enabled or disabled.
Operation Status	The actual status of this launch table entry, which can be either enabled or disabled.
Max Running	The maximum number of concurrently running scripts that may be invoked from this entry. The default value is 3. This field can be modified by directly writing into the field.
Max Completed	The default value is 3. The maximum number of finished scripts invoked from this entry in the Launch Table that are allowed to be retained in the Result Table.
Life Time	The default maximum amount of time that a script launched from this entry may run. The default value is 86,400 seconds (1 day).
Expire Time	The default maximum amount of time that information about a script launched from this entry is kept in the Result Table after the script has completed execution.

To Add a New Entry to the Launch Table

Steps

1. Access the Launch Table as described in To Access the Script Launcher Module.

2. Press mouse button 3 on the Launch Table header.

   A pop-up menu is displayed.

   

3. Choose New Row and provide all the required parameters.

   The Script Owner and Script Name values point to the script that is started from this launch button.

To Launch an Instance of a Script

Steps

1. Access the Launch Table as described in To Access the Script Launcher Module.

2. Press mouse button 3 on the row displaying the desired script name.

3. Select Launch Script.

   The script is launched.

To Stop Scripts

Steps

1. Access the Launch Table as described in To Access the Script Launcher Module.

2. Press mouse button 3 on the row displaying the script you want to stop.

   A pop-up menu appears.

3. Choose Abort Scripts.

   The script stops running.

Result Table

The Result Table lists all scripts that are currently running or have recently terminated. This table contains the following information:

• The time the script started and finished execution

• The reason the script finished executing

• The result of the script

• The remaining time the script is allowed to run

Every row in the Result Table contains the arguments passed during script invocation, the results produced by the script, and the script exit code. The Result Table also provides information about the current run state, and start and end timestamps.

The Result Table shows the attributes listed in the following table.

Table 5–3 Result Table Attributes

Attribute	Description
Run Index	A unique identifier associated with the script. The value is obtained by prepending launchName with an increasing integer. The integer starts from 0.
Arguments	The arguments supplied to the script when it started.
Exit Code	The reason why a script finished execution. The following values are possible:  None – Script is still in initializing or Running state. Halted – Script has been aborted. Successful – Script finished executing successfully. Failed – Script finished execution with an error.
Result Log	The path to the log file.
Run Control	The desired status of the script execution defined by this row (abort or noop).
Run State	The script execution status. The following values are possible:  Initializing – The script is initializing. Running – The script is running. Not Running – The script could be in this state because of successful completion, failing, or aborting. The exact reason why the script is Not Running is reflected in the Exit Code field.
Error Log	The path to the log file.
Start Time	The date and time when the execution started.
End Time	The date and time when the execution terminated.
Life Time	How long the script can execute. If the script has not terminated when this time has expired, the script is killed automatically.
Expire Time	How long this row can exist in the Result Table after the script has terminated. This attribute is the value of the Expire Time field of the Launch Table when the script was launched. A script entry is removed from the Result table when Expire Time seconds have passed since the script reached the Not Running state.

To View the Results From the Result Table

Steps

1. Access the Result Table as described in To Access the Script Repository Module.

2. In the Result Table, press mouse button 3 on a running script entry.

   A pop-up menu is displayed.

3. Choose View the Result Log to view the result log file corresponding to the selected running script.

   The Probe Viewer appears, and displays the result of the log.

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   Note –

   You can also access log files at the command line. The log files are saved in the /var/opt/SUNWsymon/SysMgmtPack/script-launcher/scripts/UserName/logs directory. The log file name includes the running instance so that the current log file is identifiable when a user runs the same script several times.

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To Delete a Row From the Result Table

Steps

1. Access the Result Table as described in To Access the Script Repository Module.

2. In the Result table, press mouse button 3 on a row.

   A pop-up menu is displayed.

3. Choose Delete Row.

   A dialog box appears to confirm or cancel the deletion.

4. Click Yes to confirm.

   Once the row has been deleted, the Run Table is automatically refreshed.