Backup and recovery frequently asked questions
This topic contains information about questions and answers about backup and recovery procedures and concepts.
Some of the answers direct you to a specific information center topic or to a section of the Recovering your system topic collection that contains the answer to your question.
Planning a backup strategy
How do I make sure that I save everything that I need to save on a regular basis?
What are the different IBM® i object types that I might need to save?
Is it possible to save only objects that have changed?
What kind of methods besides a good save strategy can I use to protect my data?
What kind of storage devices can I take advantage of?
What is the best way to manage my save media?
How does the save-while-active function work?
How can I reduce the time it takes to back up my system?
Basic backup tasks
How do I back up my entire system while I am away?
How do I back up my Domino® user information?
How do I save an independent auxiliary storage pool (ASP)?
Do I need to be in a restricted state to back up QUSRSYS?
How do I save objects that are active?
How can I determine if everything on my system is backed up?
How do I transfer objects from one system to another system?
How can I find out when an object was last saved?
How can I save and restore my objects and the associated private authorities?
Troubleshooting backup problems
Why do my backups take so long after I restart my system?
Why do my backups take longer after I upgrade to a new release?
Why do my backups take longer after I change hardware on my system?
I am backing up only changed objects, but why is my tape filling up?
Why are not all the changed objects saved when I am saving changed objects on my system?
Why are not all the objects in QUSRSYS being saved when I am saving the QUSRSYS library?
Why is my system not saving all of my libraries?
How do save commands handle damage on objects?
Preparing for a recovery
What actions do the system take when I restore user profiles?
What does the Restore Authority (RSTAUT) command do?
What steps should I follow to reload my entire system?
Basic recovery tasks
How do I reload my entire system?
What instructions should I follow if I want to reload my Licensed Internal Code?
How do I reload my operating system?
How do I restore physical database files?
How do I restore logical files?
How do I restore an individual object from tape?
How do I recover an independent ASP?
How can I restore a user-defined file system that was saved when it was mounted?
How do I restore an unmounted user-defined file system?
How can I recover or migrate a few objects when the user profiles already exist on the system?
How do I encrypt the data to a tape device?
How do I restore data that I have backed up using an encrypting tape drive?
What can I do if I lose data in an encrypted user or independent auxiliary storage pool (ASP)?
Troubleshooting recovery problems
Why is my restore process taking a very long time?
Why am I experiencing authority errors after a restore operation?
Planning a backup strategy
How do I make sure that I save everything that I need to save on a regular basis? See Knowing what to save and how often to save it.
What are the different IBM i object types that I might need to save? See Manually saving parts of your system.
Is it possible to save only objects that have changed? Yes. See Saving only changed objects.
What kind of methods besides a good save strategy can I use to protect my data? You can use Disk protection types to protect the data on your system.
What kind of storage devices can I take advantage of? See Storage solutions for different ways to store your data.
What is the best way to manage my save media? Backup, Recovery, and Media Services (BRMS) helps you implement a disciplined approach to managing your backups, and provides you with an orderly way to retrieve lost or damaged data.
How does the save-while-active function work? See Save-while-active function.
How can I reduce the time it takes to back up my system? You can take advantage of several different methods to reduce the time it takes to back up your system. Your business has unique needs, and some methods are more appropriate than others. See the following options to investigate time-saving backup techniques:
Basic backup tasks
How do I back up my entire system while I am away? To perform unattended backups, you can use one of the following options:
- See GO SAVE: Option 21 (saving the entire system) and specify a time at the Start time prompt.
- See Backing up your system for unattended full system backups.
How do I back up my Domino user
information? See the Lotus® Domino Reference Library 
for
information about saving Domino information. Backup, Recovery, and Media Services (BRMS) also
provides support for backing up Domino information.
How do I save an independent auxiliary storage pool (ASP)? See Saving independent ASPs.
Do I need to be in a restricted state to back up QUSRSYS? It is highly suggested that you back up QUSRSYS in a restricted state. However, there are other ways to fully save QUSRSYS without having to be in a restricted state. See Methods to save Q libraries that contain user data.
How do I save objects that are active? See Saving your system while it is active for information about the save-while-active function.
How can I determine if everything on my system is backed up? See Determining objects that the system saved (save messages).
How do I transfer objects from one system to another system? There are a few ways to transfer objects from one system to another system.
- You can use the ObjectConnect commands to move the objects. See Using the ObjectConnect Commands.
- You can save your objects to media, and then restore them to the other system. See Manually saving parts of your system.
See Restoring specific types of information.
How can I find out when an object was last saved? See Determining when an object was last saved.
Troubleshooting backup problems
Why do my backups take so long after I restart my system? Before an object can be saved, it must be loaded into main storage from disk storage. Often the objects that you are saving are already in main storage because you have been using the objects with your business applications. When you restart your system, all of the objects might be cleared out of main storage. Therefore, if you back up your system immediately after restarting it, the backup takes longer because all of the objects must be loaded into main storage before they can be saved.
The backup also performs additional processing the first time an object is accessed after your restart the system. The backup can run even slower if the previous restart operation was not normal.
If you want better performance in these scenarios, try the following methods:
- Avoid backups that coincide immediately after a restart.
- Access as many objects as possible between the restart and the start of the first backup. For example, submit a DSPOBJD or DSPFD. This loads more objects into main storage before a backup and limits the processing during the backup.
You can refer to Info APAR II12893 on the Support for IBM System i®.
Why do my backups take longer after
I upgrade to a new release? If you change any hardware during
the upgrade, the hardware configurations might affect backup and recovery
performance. See the chapter about save/restore performance in the System
i Performance Capabilities Reference 
. Before an object is saved, it must
be loaded into main storage from disk storage. Often the objects that
you are saving are already in main storage because you have been using
the objects with your business applications. When you upgrade your
system, all of the objects might be cleared out of main storage. Therefore,
if you back up your system immediately after upgrading it, the backup
takes longer because all of the objects must be loaded into main storage
before they can be saved.
If you want better performance in these scenarios, try the following methods:
- Avoid backups that coincide immediately after an upgrade.
- Access as many objects as possible between the upgrade and the start of the first backup. For example, submit a DSPOBJD or DSPFD. This loads more objects into main storage before a backup and limits the processing during the backup.
For more information, you can refer to Object conversions. You can also refer to the Memo to users for the release to see if the backup performs any conversions during the first backup.
Why do my backups take longer after
I change hardware on my system? When you change hardware on your
system, the hardware configuration might affect backup and recovery
performance. See the chapter about save/restore performance in the System
i Performance Capabilities Reference for information about hardware changes
that might affect performance.
I am backing up only changed objects, but why is my tape filling up? The most likely cause for this problem is that you specify *NO on the Journaled Objects (OBJJRN) parameter of the Saving Changed Objects (SAVCHGOBJ) command. The OBJJRN parameter specifies whether changes to objects currently being entered in a journal as specified on the Start Journal Physical Files (STRJRNPF) are saved. If OBJJRN(*NO), which is the default, is specified, database files currently being journaled are not saved, unless journaling is started after the specified Reference date (REFDATE) and Reference time (REFTIME) parameters on the SAVCHGOBJ command.
This ensures that changes made to a physical file before journaling starts are not lost (because they were not journaled in a journal receiver). The date and time of the last journal start can be displayed by using the Display File Description (DSPFD) command.
When you journal database files, the system uses one or more journal receivers to keep a record of changes that occur to the journaled files. If you journal database files, you probably do not want to save those physical files when you save changed objects. You should save the journal receivers rather than the physical files.
Why are not all the changed objects saved when I am saving changed objects on my system? See Determining objects that are not saved.
Why are not all the objects in QUSRSYS being saved when I am saving the QUSRSYS library? Some of the objects in QUSRSYS might be active during the backup. You might need to be in a restricted state to back up all of the objects in that library. See Methods to save Q libraries that contain user data.
Why is my system not saving all of my libraries? See Determining objects that are not saved.
How do save commands handle damage on objects? See How the system handles damaged objects during a save operation.
How can I ensure that an application that has objects in multiple libraries or directories is saved with consistent data? You can use the STRSAVSYNC command (along with the Save Object (SAV) or Save Library (SAVLIB) command) to synchronize the data across multiple libraries or directories. See Using save-while-active to synchronize the saved data and Full synchronization.
Preparing for a recovery
What actions do the system take when I restore user profiles? See What happens when you restore user profiles.
What are the advantages in using RSTUSRPRF *ALL as opposed to individual profiles? See What you should know about restoring user profiles.
What does the Restore Authority (RSTAUT) command do? Use the RSTAUT command to restore a user's private authorities to objects. See Restoring object authorities.
What steps should I follow to reload my entire system? See Recovering your system.
Basic recovery tasks
How do I reload my entire system? See Recovering your system.
What instructions should I follow if I want to reload my Licensed Internal Code? See Recovering the Licensed Internal Code.
How do I reload my operating system? See Restoring the operating system.
How do I restore physical database files? See Restoring database files.
How do I restore logical files? See Restoring logical files.
How do I restore programs? See How the system restores programs.
How do I restore an individual object from tape? See Restoring objects.
How do I recover an independent ASP? See Choosing the recovery procedure for a disk failure or disk errors and Recovering an independent auxiliary storage pool (ASP) for information about recovering an independent ASP.
How can I restore a user-defined file system that was saved when it was mounted? If a save operation includes objects from a mounted user-defined file system (UDFS), file system information is saved. You can restore a mounted UDFS by specifying the RBDMFS(*UDFS) parameter on the RST command. The RBDMFS parameter rebuilds the mounted file system during the restore operation. For more detailed information, see Saving a mounted UDFS and Restoring a mounted user-defined file system.
How do I restore an unmounted user-defined file system? See Restoring an unmounted user-defined file system.
How can I ensure that my logical files restore correctly if they are in a different library from their associated physical files ? See Sequence for restoring related objects and Verifying whether objects are restored successfully.
How can I restore the database logical files and SQL materialized query tables (MQTs) that have dependencies on other files? See Deferring the restore of dependent objects.
How can I recover or migrate a few objects when the user profiles already exist on the system? See Restoring private authorities for selected objects.
How do I encrypt the data to a tape device? See Recovering from an encrypted backup using software encryption.
How do I restore data that I have backed up using an encrypting tape drive? See Recovering from an encrypted backup using an encrypting tape.
What can I do if I lose data in an encrypted user or independent auxiliary storage pool (ASP)? See Restoring encrypted auxiliary storage pools.
Troubleshooting recovery problems
Why is my restore process taking a very long time? See the following information about restore performance:
Why am I experiencing authority errors after a restore operation? See the following information about handling authority errors after a restore operation: