HP NonStop RDF, Руководство по управлению

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option. For the timestamp to be used with the SYNCHDBTIME attribute, you specify a timestamp
following the guidelines for the INITTIME option.
When you configure a new RDF subsystem, use your existing RDF configuration file. You then
follow the guideline for an entire database synchronization operation, except that you only need
to obtain a new copy of the one file or partition.
Partial Database Synchronization Issues
There are many considerations when synchronizing selected portions of a database. You should
read this chapter carefully before attempting to perform the operation.
Typically you need to perform a partial database synchronization for either of two reasons:
• You are adding a new volume to the RDF configuration that was not previously in your
configuration.
• You have encountered a problem with a volume or a file that requires resynchronization.
As stated above, a partial database synchronization follows the same steps as those for
synchronizing an entire database, except that you only need to obtain new copies of the files (
see
Step 4 ) to be synchronized and load duplicate copies of the files or tables to be synchronized.
Also, when determining what timestamp to specify with the SYNCHDBTIME attribute, you
should follow the guidelines for the INITTIME option.
There are a variety of considerations when synchronizing portions of a database. Read the
following carefully.
Enscribe Files Without Partitions
Key-Sequenced and Relative Files
Use either Method 1 or Method 2 of Step 4 under “Synchronizing Entire Databases Online”
(page 168) to obtain a new copy of the file-set. Then use BACKUP and RESTORE (or FUP DUP)
to move the duplicate file to the backup system.
Alternatively, if you use Step 4, Method 1, you can create the duplicate file directly on the backup
system and then load it across the network, provided you have enough Expand capacity to
handle both the data being loaded and the audit being shipped to the backup system by the
extractor. If you created the duplicate file with the LIKE option and the primary file has an
alternate key file, then the file label of that duplicate file points to the alternate key file on the
primary system. You must change this to point to your alternate key file on your backup system.
Use a FUP ALTER command to alter the file label manually. For example:
FUP ALTER $DATA.TEST.PART0100,
ALTFILE ( 0, \BACKUP.$DATA.TEST.ALTF0100 )
Entry-Sequenced Files
If you use Step 4, Method 2, there are no special considerations for entry-sequenced files. You
cannot use Step 4, Method 1.
Enscribe Files With Partitions
Key-Sequenced Files with Create/Load (Step 4, Method 1)
First create a non-audited duplicate file on the primary system. You must create the entire file
with all partitions. Then, you only need to load the partition that you need. For example, suppose
the file has two partitions: $DATA1.TEST.PART0100 (primary) and $DATA2.TEST.PART0100
(secondary). Issue the following command:
FUP CREATE $DATA1.TEMP.PART0100,
LIKE $DATA1.TEST.PART0100, NO AUDIT
That command creates the two files $DATA1.TEMP.PART0100 (primary partition) and
$DATA2.TEMP.PART0100 (secondary partition).
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