Effects of system value settings on restore operations
When you prepare for a restore operation, you need to set the restore system values so that they are compatible during a restore operation.
When preparing for a restore operation, it is important to know and understand how the following system values work together to restore objects.
- Verify object signatures during restore (QVFYOBJRST)
- Convert objects during restore (QFRCCVNRST)
- Allow restore of security-sensitive objects (QALWOBJRST)
When an attempt is made to restore an object onto the system, these three system values work together as filters to determine if the object is allowed to be restored, or if it is converted during the restore. The first filter is the Verify object on restore (QVFYOBJRST) system value. It controls the restore of some objects that can be digitally signed. The second filter is the Convert objects during restore (QFRCCVNRST) system value. You use this system value to specify whether to convert programs, service programs, SQL packages, and module objects during the restore operation. It can also prevent some objects from being restored. Only objects that can get past the first two filters are processed by the third filter. The third filter is the Allow restore of security-sensitive objects (QALWOBJRST) system value. It specifies whether objects with security-sensitive attributes can be restored.
When a restore operation is performed, you must set the Force object conversion (FRCOBJCVN) parameter and the Convert objects during restore system value to compatible settings. Otherwise, you will receive an error message and the restore operation will fail. The following table identifies which settings are compatible and which ones fail.
| FRCOBJCVN parameter | QFRCCVNRST system value | Outcome of restore command |
|---|---|---|
| *SYSVAL | 0,1,2,3,4,5,6, or 7 | The Convert objects during restore (QFRCCVNRST) system value is used. |
| *NO | 0 | No objects are converted and everything is restored without conversion. |
| *NO | 1 | Only objects with validation errors are converted and everything else is restored without conversion. |
| *NO | 2-7 | Not compatible. An error message is sent to the system administrator and nothing is restored and nothing is converted. |
| *YES *RQD | 0, 1 or 2 | Only objects with validation errors or objects that require conversion to be used on the current release are converted. |
| *YES *RQD | 3-7 | Not compatible. An error message is sent to the system administrator and nothing is restored and nothing is converted. |
| *YES *ALL | 0, 1, 2, 3, 4, 5, 6 or 7 | FRCOBJCVN (*YES *ALL) overrides any QFRCCVNRST value and all objects are converted and restored if they are successfully converted. |
In order for an object to be restored successfully, the object must pass the three system values that work together during a restore operation: Verify object signatures during restore (QVFYOBJRST), Force conversion on restore (QFRCCVNRST), and Allow restore of security-sensitive objects (QALWOBJRST). However, if the Force object conversion (FRCOBJCVN) parameter and Force conversion on restore (QFRCCVNRST) system value are not compatible, no conversion occurs and nothing is restored.
Force object conversion (FRCOBJCVN)
The following are possible values for the Force object conversion (FRCOBJCVN) parameter:
- *SYSVAL
- The objects are converted based on the value of the Force conversion on restore (QFRCCVNRST) system value. This is the default value.
- *YES *ALL
- All objects are converted regardless of their current format. However, if the objects do not have the data required for machine translation, the objects are not restored. Conversion increases the time of the restore operation, but avoids the need to convert the objects when they are first used. This setting overrides the Force object conversion system value.
- *YES *RQD
- The objects are converted only if they require conversion to be used by the current operating system. If the objects require conversion but do not have the data required for machine translation, the objects are not restored. Conversion increases the time of the restore operation, but avoids the need to convert the objects when they are first used.
- *NO
- No objects are converted during the restore operation.
Convert objects during restore (QFRCCVNRST)
The following are possible values for the Convert objects during restore (QFRCCVNRST) system value:
- Level 0 (0)
- Restore all objects without conversion.
- Level 1 (1)
- Objects with validation errors are converted.
- Level 2 (2)
- Objects that require conversion to be used on the current version of the operating system or on the current machine are converted. Objects with validation errors are also converted.
- Level 3 (3)
- Objects that are suspected of having been tampered with, objects that contain validation errors, and objects that require conversion to be used on the current version of the operating system or on the current machine are converted.
- Level 4 (4)
- Objects that contain validation errors, that require conversion for use, or that are suspected of having been tampered with are converted. Objects that contain sufficient creation data and do not have a valid digital signature are also converted.
- Level 5 (5)
- Objects that contain validation errors, that require conversion for use, that are suspected of having been tampered with, or that contain sufficient creation data are converted.
- Level 6 (6)
- Objects that contain validation errors, that require conversion for use, that are suspected of having been tampered with, or that do not have a valid digital signature are converted.
- Level 7 (7)
- All objects are converted.
For all levels, if an object meets a requirement to be converted but fails conversion, it will not restore. Objects that do not need to be converted will restore without conversion. When an object is converted, the digital signature of the object will be removed. Also, any object that is converted will be changed to user state, its validation errors will be corrected, and it will no longer be suspected of having been tampered with.