RDF/IMP, IMPX, and ZLT System Management Manual

Managing RDF
HP NonStop RDF/IMP, IMPX, and ZLT System Management Manual—524388-002
5-11
TMF File Recovery Operations
TMF File Recovery Operations
Primary System
A file recovery operation occurs whenever a TMFCOM RECOVER FILES command is
issued at the primary system. A simple file recovery does not affect RDF and does
not require database resynchronization. A file recovery to a timestamp, first purge, or
TOMATPOSITION, however, does require you to stop RDF and resynchronize the
affected files.
Backup System
You can only use a simple TMFCOM RECOVER FILES command.
Stopping RDF
If the communications lines between the primary and backup systems are up, there are
two ways to stop RDF:
1. Issue a STOP RDF command on the primary system.
2. Issue a TMFCOM STOP TMF command on the primary system. After the RDF
updaters have reached the TMF shutdown record, RDF stops and then TMF stops.
If the communications lines between the two systems are down and you want to stop
RDF, you must issue the STOP RDF command on both the primary and backup
systems.
Note that stopping RDF leaves the backup database in an inconsistent state and also
leaves the audit trail file last opened by the extractor pinned.
For each shutdown procedure, the RDF receiver and updater processes write their
current context information to the RDF context file before stopping. If you restart but do
not reinitialize RDF, the product retrieves the context information from the context file.
The context information enables the RDF processes to resume processing where they
stopped before the shutdown, unless an audit trail file that RDF needs has been
purged and cannot be restored to disk.
Stopping RDF by Stopping TMF
The reason for stopping RDF by stopping TMF is to ensure that the primary and
backup databases are logically identical when the shutdown is complete (RDF has
applied all changes to the backup database). That will be the case, of course, only if all
Caution. After a file recovery to a timestamp, to a MAT position, or to first purge, the affected
files must be resynchronized with the backup database. After the databases are
resynchronized, transaction processing against the files that were affected by the file recovery
operation can proceed normally with full RDF protection. To resynchronize the database, follow
the procedures for this operation that appear in sections 6 and 7.