Progress
Version 9
Product Update Bulletin
SEQUENCE Qualifier
The SEQUENCE qualifier to RFUTIL improves your ability to maintain a hot stand-by database recovery strategy by updating the sequence number of a hot stand-by target database to expect the last
AI
extent in use at the time of the operating system copy or backup of the source database.
db-name
Specifies the database you are using.
CAUTION: RFUTIL SEQUENCE must be applied to the database prior to rolling forward any after image extents.RFUTIL SEQUENCE Example
A hot stand-by is typically maintained by first making a copy of your source database, and then regularly updating the database by rolling forward the
AI
extents from the source to the target. The preferred methods of making a copy of your database use the Progress utilities PROCOPY or PROBKUP. However, if you use your operating system commands to make a copy, the SEQUENCE qualifier to RFUTIL is available to update your target database to expect the correct after image extent in the roll forward sequence. Correcting the sequence is only necessary if there has been anAI
extent switch on your source database after the database was last marked as backed up and before the operating system copy was made.The following code sample demonstrates the steps to making a hot stand-by database using an operating system copy command. In this example, the target database does not need its sequence corrected:
In the next code example, updates to the database occur at an earlier point in the process. These updates require that the sequence of the target database be corrected prior to rolling forward an
AI
extent;
The target database must have its sequence corrected prior to attempting to apply an
AI
extent with roll forward. Roll forward disables after imaging, and it is impossible to correct the sequence after roll forward has been disabled. If the roll forward on the target database fails, re-copy from the source, use RFUTIL SEQUENCE, and then roll forward.
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