Drop invalid databases and database devices, Restore the msdb database – HP Data Protector Express Basic-Software User Manual
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4.
If login IDs or devices have been added to or dropped from the master database since the
last backup, those changes must be reapplied. Restart the server and reapply the changes
manually or from saved batch files.
5.
If databases have been created, expanded or shrunk since the last dump of master, those
databases must be dropped and then restored.
6.
If you have made many changes and have no recent dump, it is possible that by reloading
master in some cases you can regain data in user databases that has been lost. This technique
requires the use of DISK REINIT and DISK REFIT and can involve manual modifications
to the master database tables.
•
Use DISK REINIT to recreate rows in sysdevices for all database devices that have
been added after the most recent dump. DISK REINIT updates sysdevices just as DISK
INIT
does, but it does not format the physical disk file, so existing data is preserved.
•
Use DISK REFIT to recreate rows in sysusages and sysdatabases for all CREATE and
ALTER DATABASE
statements that were performed after the most recent dump.
•
DISK REFIT
scans the physical file associated with each space that is allocated to
databases. It also adds the corresponding sysdatabases entries. Some of the information
is not reconstructed perfectly.
For example, the original virtual device number is not assigned, because it is not known.
Instead, virtual device numbers are assigned sequentially. The database owner is not
extracted while scanning the physical files; ownership is set to the system administrator.
It is also not possible to determine how many sysusages entries originally existed. DISK
REFIT
inserts a separate entry for each different segment type.
•
When this is done, correct the entries made by DISK REFIT to sysdatabases and
sysusages (if desired) and also add to syslogins any login IDs that were not retained.
Then shut down and restart SQL Server.
CAUTION:
Capturing the latest changes made to a database by using DISK REFIT and
DISK REINIT
to recreate the master database is possible, but it is preferable to keep the
master database current by dumping it after creating or altering databases. Using DISK
REFIT
and DISK REINIT is a complicated process that can result in data loss because many
of the changes made to a database often must be reconstructed manually in the master
database. If you feel this technique is necessary, contact your primary support provider before
beginning the recovery process.
Drop invalid databases and database devices
•
Use the SQL Enterprise manager to drop any invalid database devices and databases from
the newly restored master database.
NOTE:
If you are recovering from a disaster where you have lost a database device file, the
master database you have just restored still contains a reference to it. Data Protector Express will
not be able to restore any databases contained on the database device until the file is restored or
the database device is dropped. If the database device is dropped, Data Protector Express will
automatically recreate the device when a database contained on the device is restored.
Restore the msdb database
When restoring the msdb database, keep the following considerations in mind:
•
The msdb database supports SQL Executive and provides a storage area for scheduling
information. The schedules that you implement using SQL Enterprise Manager are maintained
in the msdb database. This includes such things as the tasks that you schedule from the Task
Scheduling window, the automatic backups you schedule from the Database Backup/Restore
Working with Microsoft SQL Server
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