HP OpenVMS System Manager's Manual, Volume 2:...

Managing System Parameters

Automating AUTOGEN Reports

Managing System Parameters with SYSGEN

Managing System Parameters with SYSMAN  

HP recommends that you use AUTOGEN to modify system parameters. For more information, see Modifying System Parameters with AUTOGEN. To view system parameters for a group of nodes or change parameters temporarily, use the System Management utility (SYSMAN).

You can use SYSMAN to manage system parameters as follows:

Task	For More Information
Show parameter values	Showing Parameter Values with SYSMAN
Modify current values in the parameter file	Modifying a Parameter File with SYSMAN
Modify active values on a running system1	Modifying Active Values with SYSMAN

SYSMAN provides the commands and functions shown in SYSMAN PARAMETERS Commands.

Table 3   SYSMAN PARAMETERS Commands

Command	Function
PARAMETERS SHOW	Displays parameter values. Requires the name of the parameter.
PARAMETERS USE	Reads a set of parameters from memory or disk into the work area for inspection or modification. Requires a file name or the additional parameters ACTIVE or CURRENT.
PARAMETERS SET	Changes parameter values only in the work area; more permanent modification requires the PARAMETERS WRITE command. Requires the name and value of the parameter.
PARAMETERS WRITE	Writes the content of the work area to memory or to disk. Requires a file name or the additional parameters ACTIVE or CURRENT.

For more information about the temporary work area, see the next section.

Understanding Parameter Values and SYSMAN  

It helps to understand the different system parameter values explained in Default, Current, and Active Values. Briefly, current values are stored in the default parameter file on disk. Active values are stored in memory and are used while the system is running. In addition to these values, SYSMAN writes a temporary copy into its own work area on disk. SYSMAN Temporary, Active, and Current Parameter Values illustrates these different sets of values and how SYSMAN commands affect them. In this figure:

1. WRITE ACTIVE writes temporary parameter values to memory.
2. USE ACTIVE reads values from memory into the work area, where you can modify them.
3. WRITE CURRENT writes temporary parameter values to disk, where they become current values. They become active the next time the system boots.
4. USE CURRENT reads the current values from disk into the work area, where you can modify them.

Figure 2  SYSMAN Temporary, Active, and Current Parameter Values

During a typical session, you can display and change values in the following sequence:

1. Read values into SYSMAN's temporary work space with the USE command. USE ACTIVE reads in active values. USE CURRENT reads in current values.
2. Display the parameter values with the SHOW command.
3. Change a value with the SET command. You must use the WRITE command to activate the value.
4. Make the change effective with the WRITE command:
   • WRITE ACTIVE writes the value to the set of active values. (You can change an active value only if the parameter is a dynamic parameter.)
   
   
   
   • WRITE CURRENT writes the value to the set of current values.

For a list of all the system parameters, refer to the HP OpenVMS System Management Utilities Reference Manual.

Showing Parameter Values with SYSMAN  

Use the SYSMAN command PARAMETERS SHOW to display parameter values for all the nodes in a cluster.

Examples

1. The following example shows one method to display information about parameters. In this case, using the /LGI qualifier displays all login security control parameters. You can display many categories of parameters, such as /ACP, /ALL, and /SPECIAL. Refer to the HP OpenVMS System Management Utilities Reference Manual for a complete list of parameters and parameter categories.

   $ RUN SYS$SYSTEM:SYSMAN
   SYSMAN> PARAMETERS SHOW/LGI
   
   Parameters in use: Active
   Parameter Name            Current    Default     Min.     Max.     Unit  Dynamic
   --------------            -------    -------    -------  -------   ----  -------
   LGI_BRK_TERM                    0          1         0         1 Boolean    D
   LGI_BRK_DISUSER                 0          0         0         1 Boolean    D
   LGI_PWD_TMO                    30         30         0       255 Seconds    D
   LGI_RETRY_LIM                   3          3         0       255 Tries      D
   LGI_RETRY_TMO                  20         20         0       255 Seconds    D
   LGI_BRK_LIM                     5          5         0       255 Failures   D
   LGI_BRK_TMO                   300        300         0        -1 Seconds    D
   LGI_HID_TIM                        300         300           0         -1 Seconds      D 

2. The following example invokes SYSMAN and specifies the environment to be the local cluster, which consists of NODE21 and NODE22. The example also displays the active value for the LGI_BRK_TMO parameter, which controls the number of seconds that a user, terminal, or node is permitted to attempt login. In this case, it is 600.

   $ RUN SYS$SYSTEM:SYSMAN
   SYSMAN> SET ENVIRONMENT/CLUSTER
   %SYSMAN-I-ENV, Current command environment:
      Clusterwide on local cluster
      Username MORIN    will be used on nonlocal nodes
   SYSMAN> PARAMETERS SHOW LGI_BRK_TMO
   
    
   Node NODE21:   Parameters in use: ACTIVE
   Parameter Name         Current   Default   Minimum    Maximum Unit  Dynamic
   --------------         -------   -------   -------    ------- ----  -------
   LGI_BRK_TMO                600       300         0         -1 Seconds     D
    
   Node NODE22:   Parameters in use: ACTIVE
   Parameter Name         Current   Default   Minimum    Maximum Unit  Dynamic
   --------------         -------   -------   -------    ------- ----  -------
   LGI_BRK_TMO                600       300         0         -1 Seconds     D
   

Modifying a Parameter File with SYSMAN  

Use the SYSMAN command PARAMETERS WRITE to write system parameter values and the name of the site-independent startup command procedure to your choice of parameter file or the current system parameter file on disk.

The PARAMETERS WRITE CURRENT command sends a message to OPCOM to record the event, unless you have changed the system message format with the DCL command SET MESSAGE.

The PARAMETERS WRITE CURRENT command writes all of the active or current parameter values--not just the one you may be working on--to disk.

1. The following example creates a new parameter specification file:

   SYSMAN> PARAMETERS WRITE SYS$SYSTEM:NEWPARAM

2. When used with the PARAMETERS SET command, the PARAMETERS WRITE command modifies the current system parameter file on disk:

   SYSMAN> PARAMETERS SET LGI_BRK_TMO 300
   SYSMAN> PARAMETERS WRITE CURRENT

Modifying Active Values with SYSMAN  

Using the SYSMAN commands PARAMETERS SET, PARAMETERS WRITE, and PARAMETERS USE enables you to modify active parameter values.

Modifying active values immediately affects dynamic parameters by changing their values in memory. Appendix C of the HP OpenVMS System Management Utilities Reference Manual identifies dynamic parameters, as does the SYSMAN command PARAMETERS SHOW/DYNAMIC. Values for nondynamic parameters cannot be changed while the system is running.

Modifying active values does not affect current values in the system parameter file on disk, because the next time you boot the system, the values on disk are established as the active values.

If you set new active parameter values and you want to use the new values for subsequent boot operations, write the new values to the current parameter file with the PARAMETERS WRITE CURRENT command, as shown in the Examples section.

Parameter values modified with SYSMAN will be overridden by the AUTOGEN command procedure. To keep parameter modifications made with SYSMAN, edit the file SYS$SYSTEM:MODPARAMS.DAT as explained in Controlling AUTOGEN's Parameter Settings with MODPARAMS.DAT to specify the new parameter values.

1. The following example changes the LGI_BRK_TMO value to 300 in the work area, writes this change into memory as an active value, and displays the active value:

   SYSMAN> PARAMETERS SET LGI_BRK_TMO 300
   SYSMAN> PARAMETERS WRITE ACTIVE
   SYSMAN> PARAMETERS SHOW LGI_BRK_TMO
    
   Node NODE21:   Parameters in use: ACTIVE
   Parameter Name         Current   Default   Minimum    Maximum Unit  Dynamic
   --------------         -------   -------   -------    ------- ----  -------
   LGI_BRK_TMO                300       300         0         -1 Seconds     D
    
   Node NODE22:   Parameters in use: ACTIVE
   Parameter Name         Current   Default   Minimum    Maximum Unit  Dynamic
   --------------         -------   -------   -------    ------- ----  -------
   LGI_BRK_TMO                300       300         0         -1 Seconds     D
   

2. The following example calls the current parameter values, including LGI_BRK_TMO, from disk to the work area, then displays LGI_BRK_TMO. In this example, the current value on disk is 600.

   SYSMAN> PARAMETERS USE CURRENT
   SYSMAN> PARAMETERS SHOW LGI_BRK_TMO
   
    
   Node NODE21:   Parameters in use: CURRENT
   Parameter Name         Current   Default   Minimum    Maximum Unit  Dynamic
   --------------         -------   -------   -------    ------- ----  -------
   LGI_BRK_TMO                600       300         0         -1 Seconds     D
    
   Node NODE22:   Parameters in use: CURRENT
   Parameter Name         Current   Default   Minimum    Maximum Unit  Dynamic
   --------------         -------   -------   -------    ------- ----  -------
   LGI_BRK_TMO                600       300         0         -1 Seconds     D
   

3. The next example writes the LGI_BRK_TMO value of 600 from the work area to memory, where it becomes the active value on the running system. Note that the command PARAMETER WRITE ACTIVE writes all the parameter values from the work area into memory, not just the value of LGI_BRK_TMO.

   SYSMAN> PARAMETERS WRITE ACTIVE
   SYSMAN> PARAMETERS USE ACTIVE
   SYSMAN> PARAMETERS SHOW LGI_BRK_TMO
   
    
   Node NODE21:   Parameters in use: ACTIVE
   Parameter Name         Current   Default   Minimum    Maximum Unit  Dynamic
   --------------         -------   -------   -------    ------- ----  -------
   LGI_BRK_TMO                600       300         0         -1 Seconds     D
    
   Node NODE22:   Parameters in use: ACTIVE
   Parameter Name         Current   Default   Minimum    Maximum Unit  Dynamic
   --------------         -------   -------   -------    ------- ----  -------
   LGI_BRK_TMO                600       300         0         -1 Seconds     D
   

1	Applies only to dynamic system parameters.

( Number takes you back )

Automating AUTOGEN Reports

Managing System Parameters with SYSGEN