The backup file

The backup file is set up completely new for each backup run, if it does not already exist. If it does exist, it can be overwritten according to the wishes of the user while still retaining its file protection attributes. It is not possible to append to an existing backup file over several backup runs. Backup files can be saved and assigned protection attributes in the same way as normal files with HSMS/ARCHIVE.

A guards administrator can make a backup file that contains the complete guards inventory of a pubset available to every system member, since nonprivileged users can only access their own guards. However, it is recommended that the backup file is assigned additional access protection in this case. Backup files that are used in rotation for new backup states should also be assigned the DESTROY-BY-DELETE protection attribute to ensure that the old data is always destroyed after a new backup run.

The following example illustrates how a recommendable protection can be set up for a backup file that is accessible throughout the system:

/CREATE-GUARD GSAVE-R —————————————————————————————————————————————————  (1)

/ADD-ACCESS-CONDITIONS GSAVE-R -

/   ,SUBJECT=*USER(TSOS),ADMISSION=*YES ———————————————————————————————  (2)
/ADD-ACCESS-CONDITIONS GSAVE-R -

/   ,SUBJECT=*OTHERS,ADMISSION=*PARAMETERS -

/    (PROGRAM=*MODULE(LIBRARY=$TSOS.SYSLNK.GUARDS-SAVE.040 - ——————————  (3)
/                    ,ELEMENT=SAVELLM -

/                    ,VERSION=*ANY))

/CREATE-GUARD GSAVE-W —————————————————————————————————————————————————  (4)
/ADD-ACCESS-CONDITIONS GSAVE-W -

/   ,SUBJECT=*USER(TSOS),ADMISSION=*YES ———————————————————————————————  (5)

/ADD-ACCESS-CONDITIONS GSAVE-W -

/    ,SUBJECT=*OTHERS,ADMISSION=*NO ———————————————————————————————————  (6)

/MOD-FILE-ATTRIBUTES GUARDS-SAVE.BACKUP – —————————————————————————————  (7)

/   ,PROTECTION=*PARAMETERS -
/     (GUARDS=*PARAMETERS -

/     (READ=GSAVE-R  -

/     ,WRITE=GSAVE-W -
/     ,EXEC=*NONE) -

/ ,DESTROY-BY-DELETE=*YES)

(1)	Set up a guard for defining the read access conditions.
(2)	TSOS is to get unrestricted read access. This access can also alternatively be made available to the guard administrator user ID.
(3)	Read access to the backup file is only to be allowed with the GUARDS-SAVE program for all other user IDs.
(4)	Set up a guard for defining the write access conditions.
(5)	TSOS is to get unrestricted write access. This access can also alternatively be made available to the guard administrator user ID.
(6)	Write access to the backup file is to be forbidden for all other user IDs.
(7)	Assign protection attributes to the backup file.The guards that were set up are activated to protect the backup file.