RDF/IMP and IMPX System Management Manual (RDF 1.4+)

Installing and Configuring RDF
HP NonStop RDF/IMP and IMPX System Management Manual—524388-001
3-16
Online Product Initialization
1. If you want to install a new version of the RDF product and you cannot afford to
stop TMF even momentarily to get a TMF shutdown timestamp.
2. If you are running RDF and encounter a problem for which you would like to
reinitialize it without having to resynchronize your databases.
Determining a Valid inittime Value
When using the INITTIME parameter, it is important that you specify a valid inittime
value.
To do so, first issue a STATUS RDF command and take note of the highest updater
RTD time. Then round that RTD time up to the next higher minute (0:43 becomes 1:00,
1:27 becomes 2:00, 3:04 becomes 4:00, and so forth). Finally, subtract that rounded-
up time from the current system time shown in the status display.
inittime := (current-system-time — rounded-highest-updater-RTD-time)
RDFCOM then subtracts an additional three minutes from the specified timestamp.
This is to ensure that the extractor’s starting position is at a point in the MAT where
RDF had previously sent audit information to the backup system and the updaters had
applied it to the backup database. This practice guarantees that no audit information
will be lost during initialization.
When you include the INITTIME parameter in the INITIALIZE RDF command,
RDFCOM initiates a backward scan of the MAT searching for the first commit or abort
record whose timestamp is less than the specified inittime . When RDF is
subsequently restarted, some of the audit information will be reapplied to the backup
database. This does not cause any inconsistencies between the primary and backup
databases, but rather ensures that they stay completely synchronized with one
another.
Special Considerations
When using this form of the INITIALIZE RDF command, there are three special cases
which you might encounter.
Enscribe Create Records
If the previous version of RDF performed an Enscribe create operation on the backup
system prior to execution of the INITIALIZE RDF command and the extractor’s restart
position in the MAT precedes the associated Enscribe create record in the MAT, the
updater processing that record will report a File System error 10 (File Already Exists)
and you must purge the existing file. The updater will continue to report the error until
you have purged the file.
Stop-RDF-Updater Records
Stop-RDF-Updater records in the MAT are associated with committed SQL DDL
operations performed on the primary system with the SHARED ACCESS option.