RDF/IMP, IMPX, and ZLT System Management Manual

Entering RDFCOM Commands
HP NonStop RDF/IMP, IMPX, and ZLT System Management Manual—524388-002
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Command Overview
If you initialize RDF to the timestamp corresponding to Step b, you should restore
on the backup system a copy of the primary system database taken at Step b.
•
Initialize RDF at the most recent TMF shutdown point. If you initialize RDF at an
earlier shutdown point, RDF operations will start at that point but will shut down
when the next TMF shutdown point is reached. In this case, you must restart RDF
quickly so that operations on the backup system do not fall behind those on the
primary system. If you choose to initialize RDF at a TMF shutdown point that is not
the most recent, watch the RDF event messages for the RDF shutdown message
and then restart RDF immediately.
•
If you include the TIMESTAMP option in the INITIALIZE RDF command, use the
following guidelines to determine when you must restore the backup database:
•
If you are going to start RDF with UPDATE ON, restore the database to the
backup system before you start RDF.
•
If you are going to start RDF with UPDATE OFF, you do not have to restore
the database. However, if the need for an RDF takeover arises, you must then
restore the database on the backup system before you issue the TAKEOVER
command.
•
If you include the TIMESTAMP, INITTIME, or SYNCHDBTIME options in the
INITIALIZE RDF command, it is suggested that all MAT files are present from the
current file to the file containing the TMF shutdown record or the commit/abort
record with a timestamp less than the specified timestamp. If RDFCOM tries to
open a nonexistent file, RDFCOM can trigger restoration of the missing audit trail
files from tape or disk based on your response to a prompt message. Therefore,
not every file in the MAT must be present, from the initial file to the current file. For
example, if the current file is AA000010 and the shutdown record is in AA000009,
only files AA000009 and AA000010 need be present.
•
In any event, if you plan to enable updating on the backup system as part of the
new configuration, ensure that the primary and backup databases are logically
identical before entering the INITIALIZE RDF command. For more information
about database synchronization, see Understanding Database States in section 6.
Examples
The following INITIALIZE RDF command, issued on the primary system, \LON,
initializes the subsystem to 2:30 pm, January 12, 2004:
]INITIALIZE RDF, BACKUPSYSTEM \CHI, TIMESTAMP 12JAN2004 14:30
Do you wish to proceed? [Y/N] Y
Please wait while RDF searches for the specified timestamp.
TMF shutdown at 12JAN2004 14:30 has been found. RDF will
start at RBA: 376275 MAT file: $AUDIT.ZTMFAT.AA000414
Do you still wish to start at this point? [Y/N] Y