First, I totally agree with you about the lack of documentation of how to restore from an IDB Backup
This is from a document that is still being written. Please be sure that al these steps were followed
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During online Internal Database restore, the basic IDB parts (CDB, MMDB, SMBF) can only be
restored to a location different from the original, while the Cell Manager configuration data and the
Detail Catalog Binary Files (DCBF) part of the IDB can be either restored to their original or different
locations.
Steps
1. In the Context List, click
Restore.
2. In the Scoping Pane, expand Restore Objects, and then expand Internal Database.
3. Expand the Cell Manager from where the IDB was backed up from, and click
Internal Database.
4. On the Internal Database property page, to restore the basic Internal Database parts, keep the
Restore Internal Database option selected. The basic parts of the IDB are the Catalog
Database (CDB), the Media Management Database (MMDB), and the Session Messages
during the restore, and the location to which the basic IDB parts should be restored to.
Additionally, decide whether to perform the Internal Database recovery using the archived log
files, and if the restored IDB should be put into use as the new Internal Database of the cell.
I would ask that you not attempt to restore the Archive Logs at this time
5. Select
Restore catalog binary files to restore the DCBF part of the IDB, and choose its
restore location: original or custom.
6. Specify whether Data Protector should restore the IDB to a specific point in time which is not
the time of the latest IDB backup image creation. In this case, the basic Internal Database part
will be restored to the latest backed up state before the specified time.
Do not use Point in Time Restore
7. On the Configuration Files property page, make your choice about the restore of the Cell
Manager configuration data. If this data is selected for restore, you should also specify its
backup object version, the restore location, and decide how Data Protector will handle the
configuration files that still exist at their original location.
This should have also restored the UserList, which you said was missing in your previous attempt
8. On the Options property page, specify the optional pre-exec and post-exec commands for the
restore session.
9. On the Devices property page, make your choice about which devices to use in the session.
10. On the Media property page, review the backup media that will be used for restoring the IDB.
Optionally, adjust their priorities Data Protector will consider during the session.
11. From the Actions menu, select
Start Restore, or in the Results Pane, click Restore.
12. Click Finish.
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Basically, I want to see if just restoring from the last full IDB backup will let your previous sessions