RDF/IMP and IMPX System Management Manual (RDF 1.3+)

Managing RDF
Compaq NonStop™ RDF/IMP and IMPX System Management Manual—522204-001
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TMF File Recovery Operations
4. From the backup system, restart TMF on the backup system by entering this
command through TMFCOM:
~START TMF
5. From the primary system, resume updating of the backup database by entering this
command through RDFCOM:
]START UPDATE
Volume Recovery Processing
A volume recovery operation occurs whenever a TMF data volume goes down and then
is subsequently reenabled by a TMFCOM ENABLE DATAVOLS command issued at the
primary system.
RDF handles volume recovery automatically. The updater processes apply only the audit
data for committed transactions to the backup database. Updater processes never apply
changes backed out by a volume recovery operation to the backup database, because no
commit records are associated with such changes.
Volume Recovery Failure
RDF cannot recover from a TMF subsystem crash if TMF cannot successfully perform
volume recovery. After TMF crash has been resolved, you must perform the following
tasks:
1. Resynchronize the primary and backup databases, following procedures explained in
sections 6 and 7.
2. Reinitialize RDF.
TMF File Recovery Operations
For D30 and later versions of TMF, 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 either a timestamp or a purged record, however, does require you to stop
RDF and resynchronize the affected files.
Caution. After a file recovery to a timestamp, 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.