Changing the Backup Policy

Perform the following steps to get to the Backup Policy display:

Type GO WRKPCYBRM *BKU at a command line and press Enter.

Take option 1 (Display or change backup policy) from the Backup Policy menu.

                         Change Backup Policy                        RCHAS400  
                                                                               
                                                                               
 Type choices, press Enter.                                                    
                                                                               
 Media policy for full backups  . . . . . *SYSPCY     Name, F4 for list        
 Media policy for                                                              
    incremental backups . . . . . . . . . *SYSPCY     Name, F4 for list        
 Backup devices . . . . . . . . . . . . . *SYSPCY     Name, F4 for list        
                                                                               
                                                                               
                                                                               
 Default weekly activity  . . . . . . . . FFFFFFF     SMTWTFS(F/I)             
 Incremental type . . . . . . . . . . . . *CUML       *CUML, *INCR             
 Force full backup days . . . . . . . . . *NOMAX      0-365, *NOMAX            
 Sign off interactive users . . . . . . . *SYSPCY     *YES, *NO, *SYSPCY       
 Sign off limit . . . . . . . . . . . . . *SYSPCY     0-999 minutes, *SYSPCY   
 Save journal files when saving                                                
    changed objects . . . . . . . . . . . *NO         *YES, *NO                
                                                                               
                                                                        More...
 F3=Exit    F4=Prompt    F5=Refresh    F9=System policy                        
 F12=Cancel

As you can see, the backup policy shares several parameters with the system policy. You can override the shared prompts on an as-needed basis or to customize your backups as desired.

Following are brief descriptions of the parameters you are most likely to change:

The Default weekly activity value specifies the type of backup you want to perform each day of a seven-day week. For example, you might want BRMS to perform a full backup (F) on a Friday, and an incremental backup (I) on the other nights of the week. Or BRMS could perform a full backup every night. Leaving one of the days blank indicates that you do not want any backups performed on that day.

The Incremental type field allows you to specify the type of incremental backup you want BRMS to perform. To save all changes since the last full backup, specify *CUML in this field. To save changes since the last time BRMS performed an incremental save, specify *INCR. CUML saves make recovery activities easier and shorter, while INCR saves can make your save windows shorter. IBM recommends that you keep the default (*CUML) to provide better protection for important data.

The Force full backup days field allows you to force full saves rather than a save of changed objects if no save has occurred within the specified number of days.

The Save journal files while saving changed objects field specifies whether to save changes to objects that you entered in a journal. The default for this value is *NO, which indicates reliance on journaled receivers to retrieve changes during the recovery. IBM recommends that you change this default to *YES for ease of use, and to reduce the number of recovery steps. You should be aware, however, that using *YES increases your save time. If *YES is specified, all journaled objects are saved, not just journaled files.

Page down to see additional attributes.

                         Change Backup Policy                        RCHAS400   
                                                                                
                                                                                
 Type choices, press Enter.                                                     
                                                                                
 Automatically backup                                                           
     media information  . . . . . . . . . *LIBE       *LIB, *OBJ, *NONE         
 Save access paths  . . . . . . . . . . . *YES        *YES, *NO                 
 Save contents of save files  . . . . . . *YES        *YES, *NO                 
 Save spooled file data . . . . . . . . . *NONE       *NONE, *ALL               
 Data compression . . . . . . . . . . . . *DEV        *DEV, *YES, *NO           
 Data compaction  . . . . . . . . . . . . *DEV        *DEV, *NO                 
 Target release . . . . . . . . . . . . . *CURRENT    *CURRENT, *PRV            
 Clear  . . . . . . . . . . . . . . . . . *NONE       *NONE, *ALL, *AFTER       
 Object pre-check . . . . . . . . . . . . *NO         *YES, *NO                 
 Append to media  . . . . . . . . . . . . *NO         *YES, *NO                 
 End of tape option . . . . . . . . . . . *UNLOAD     *UNLOAD, *REWIND, *LEAVE  
 Use optimum block size . . . . . . . . . *DEV        *DEV, *YES, *NO           
                                                                                
                                                                                
                                                                        More... 
 F3=Exit    F5=Refresh    F9=System policy    F12=Cancel

The Automatically backup media information parameter specifies the level at which you want BRMS to save media information. BRMS uses the media information to assist in the restore process. The default level is *LIB. Other options are *OBJ and *NONE. To retain media information at the object level, you should indicate that preference at this field, and also at the Retain Object Detail parameter (change value to *YES). The Retain Object Detail parameter is on the Edit Control Group Entries display. If you do not specify *OBJ in the Automatically backup media information field, and *YES in the Retain object detail field, BRMS may not save the information at *OBJ level for that job.

Note:

Retaining object level detail can considerably increase your disk space, and your save and restore times. Keep in mind that you can restore an individual object without object level information if you know the name of the object. You can search your save history for the library using the Work with Media Information (WRKMEDIBRM) command. Normally, the default value, *LIB, is satisfactory for most customers.

The Save access paths field allows you to save the access paths associated with your logical and physical files. The value in this field indicates whether to save the logical file access paths that are dependent on the physical files BRMS saves. BRMS saves access paths only if you also save all of the members on which the access paths are built. BRMS sends informational messages that indicate the number of logical access paths that were saved with each physical file. All physical files on which the access paths are built must be in the same library. This parameter does not save logical objects; it only controls the saving of the access paths.

The default value established for the Save access paths field in the backup policy is *YES. You can use the save access paths default that is established here for a backup control group. Or you can override the value at the Change Backup Control Group Attributes display. IBM recommends that you save the access paths, even when it is time-consuming. If you do not, you run the risk of losing system availability if you need to recover the file or the system after a disaster. Saving the access paths increases the save time, but decreases your recovery time, thereby increasing system availability. See the Recovering your system book for more information about the restoration of saved paths.

Note:

If BRMS performs both full and incremental saves, it restores the full saves first, then the incremental. If you do not save your access paths, they will likely be rebuilt twice, once during the restore from the full backup and then again during the restore of the incremental saves. Use the Edit Rebuild Access Path command (EDTRBDAP) to perform the rebuild right after the restoration of the full save has completed. You can then restore the incremental saves and use the EDTRBDAP command to change the sequence number.

The Save spooled file data field allows you to save the spooled files and the attributes of these files concurrently when saving output queues.

The Append to media value specifies whether to add files on current media with active files or to begin a new volume. If you specify *YES, BRMS writes the files to the volume that immediately follows the last active file. This allows you to maximize media usage. However, if you want to separate data on separate tapes, you should specify *NO.

When you select *YES at the Append to media prompt, BRMS takes the following steps to select the volumes to append:

When selecting volumes for media libraries, BRMS determines if the last volume that is used can also be used for the append operation. The media class is the determining factor. When selecting volumes for stand-alone drives, BRMS issues message BRM1472, which nominates suitable candidate volumes.
BRMS selects an active volume with attributes that match those in the appropriate media policy. BRMS uses the following to check if the volume is available for appending:
- Same media class
- Same storage location
- Same expiration date
- Owned by the requesting system
- Same move policy
- Same secure attribute
If BRMS cannot find a volume that meets the criteria above, it selects a volume with an earlier expiration date, starting with the earliest.
If BRMS cannot select a volume with an earlier expiration date, it selects an expired volume from the system.
If BRMS fails to find a volume up to this point, it will try to select an expired volume from another system.
BRMS will never select a volume that has been flagged in error (expiration of volume is *ERR).

While these are the parameters you are most likely to use, you should also be familiar with the other parameters and values on the backup policy display.

Note:

In addition to the backup policy itself, you can also access the Work with items to omit from backup display from the Backup Policy menu. Because the items you are likely to omit are in control groups, you can find information about how to use this display in the following section.

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