o To use the RMU Restore command for a database, you must have
the RMU$RESTORE privilege in the root file access control
list (ACL) for the database or the OpenVMS SYSPRV or BYPASS
privilege.
o The RMU Restore command provides four qualifiers, Directory,
Root, File, and Snapshots, that allow you to specify the
target for the restored files. The target can be just a
directory, just a file name, or a directory and file name.
If you use all or some of these four qualifiers, apply them as
follows:
- Use the Root qualifier to indicate the target for the
restored database root file.
- Use local application of the File qualifier to specify the
target for the restored storage area or areas.
- Use local application of the Snapshots qualifier to specify
the target for the restored snapshot file or files.
- Use the Directory qualifier to specify a default target
directory. The default target directory is the directory
to which all files not qualified with the Root, File, or
Snapshot qualifier are restored. It is also the default
directory for files qualified with the Root, File, or
Snapshot qualifier if the target for these qualifiers does
not include a directory specification.
Note the following when using these qualifiers:
- Global application of the File qualifier when the target
specification includes a file name causes RMU Restore to
restore all of the storage areas to different versions
of the same file name. This creates a database that is
difficult to manage.
- Global application of the Snapshot qualifier when the
target specification includes a file name causes RMU
Restore to restore all of the snapshot files to different
versions of the same file name. This creates a database
that is difficult to manage.
- Specifying a file name or extension with the Directory
qualifier is permitted, but causes RMU Restore to restore
all of the files (except those specified with the File
or Root qualifier) to different versions of the same file
name. Again, this creates a database that is difficult to
manage.
See Example 17.
o When you restore a database into a directory owned by a
resource identifier, the ACE for the directory is applied
to the database root file ACL first, and then the Oracle RMU
ACE is added. This method is employed to prevent database
users from overriding OpenVMS file security. However, this can
result in a database which you consider yours, but to which
you have no Oracle RMU privileges to access. See the Oracle
Rdb Guide to Database Maintenance for details.
o If a backup file to tape is created using a single tape
device, it must be restored using a single tape device; it
cannot be restored using multiple tape devices.
NOTE
An incremental backup file created for a database running
under one version of Oracle Rdb cannot be applied if
that database has been restored under another version of
Oracle Rdb. For example, if you do the following, step 6
fails with the error message, "XVERREST, Cross version
RESTORE is not possible for by-area or incremental
functions":
1. Apply a full backup operation to a Version 7.1
database.
2. Apply updates to the database.
3. Perform an incremental backup operation on the
database.
4. Move backup files to a system running Oracle Rdb
Version 7.2.
5. Restore the database by using the full backup file.
6. Attempt to apply the incremental backup file created
in step 1.
o If you apply an incremental backup file, you must specify the
Norecovery qualifier when you issue a full RMU Restore command
for the corresponding full backup file.
o If you mistakenly attempt to restore a backup file in a
version of Oracle Rdb that is earlier than the version for
which the backup file was created, you might receive INVRECTYP
errors and your operation will probably terminate with an
access violation (ACCVIO) exception. If you receive this
error, check the version of the backup file and the version
of Oracle Rdb you are running. Be sure the environment version
matches, or is greater than, the version under which the
backup file was created.
o RMU Restore might create an .rdb file and .rda files when it
starts up. If you specify the Log qualifier, these files will
be noted in the log file. These are not database files until
the end of the operation when they have been populated with
the backed-up contents. Therefore, if the restore operation
aborts or is stopped using Ctrl/Y, you must delete these
unpopulated files by using the DCL DELETE command. You know
which files to delete by the contents of the backup file and
the form of the command issued, or by examining the output
in the log file if you specified the Log qualifier. Deleting
the files usually requires OpenVMS privileges. Until they are
restored, these files are not a database, and Oracle RMU or
SQL operations do not function with them.
o RMU Restore preserves any area reservations and after-image
journal (.aij) file reservations that exist in the backed-up
database.
o If you restore a database without its root file ACL (using the
Noacl qualifier with the RMU Restore command, for example),
a user who wants to create ACL entries for the database must
have the OpenVMS SECURITY or BYPASS privilege.
o The RMU Restore command with the Area and Online qualifiers
requires exclusive access to the area files being restored.
The RMU Restore command with the Area, Online, and Just_
Corrupt qualifiers requires exclusive access to only the pages
being restored.
o There are no restrictions on the use of the Nospams qualifier
with storage areas that have a mixed page format, but the use
of the Nospams qualifier typically causes severe performance
degradation. The Nospams qualifier is useful only where
updates are rare and batched, and access is primarily by
database key (dbkey).
o The RMU Restore command automatically uses the RMU Convert
command when restoring the database to a system with a
more recent version of Oracle Rdb software. When this is
done, the metadata in the Oracle Rdb database changes and
invalidates incremental backup files from the previous
version. By default, no areas are reserved and one .aij file
is reserved. (You can override the after-image journal default
reservation by using the Aij_Options qualifier.) See Convert
for information on the versions of Oracle Rdb that the Convert
command supports.
o Always back up your Oracle Rdb databases as recommended in the
Oracle Rdb Installation and Configuration Guide just prior to
installing a newer version of Oracle Rdb software. The last
backup file made prior to converting to a more recent version
of Oracle Rdb should be a full and complete backup file.
o See the Oracle Rdb Guide to Database Maintenance for
information on the steps RMU Restore follows in tape label
checking when you restore a database from tape.
o RMU Restore might initialize the SPAM thresholds for some data
pages of some storage areas that have a uniform page format
to values that are not acceptable to the RMU Verify command.
This occurs when some of the data pages in a logical area are
restored before the logical area definition (Area Inventory).
This is not a frequent occurrence, and when it does happen,
the consequences are usually cosmetic (the RMU Verify command
issues a warning message for each page affected). However, if
many pages are affected, the volume of warnings can cause you
to overlook a real problem. Moreover, in some cases, this can
result in additional I/O operations when new data is stored in
an affected table.
As a workaround, you can use the RMU Repair command to
reconstruct the SPAM pages in one or more storage areas. The
RMU Repair command corrects the condition caused by the RMU
Restore command as well as other SPAM page corruptions. See
the help entry for the RMU Repair command for more information
on the RMU Repair command.