HP NonStop RDF, Руководство по управлению

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• Volume names are not allowed in mapping strings. If the updater detects a $ character, it
logs an error.
• Reserved names are not allowed in mapping strings. See the examples of invalid mapping
strings listed below.
• When two or more mapping rules are present in a mapfile, the rule listed first always takes
precedence if it fits. For example, assume these two mapping strings are present:
MAP NAMES SUBVOL1.* TO SUBVOL2.*
MAP NAMES SUBVOL*.* TO SUBVOL3.*
The incoming source file is from subvolume SUBVOL1 on the primary system, its changes
are replicated to the destination subvolume SUBVOL2 on the backup system instead of
SUBVOL3. If the first mapping rule cannot be applied, a subsequent mapping rule that fits
will be applied, as when changes to the incoming source file from the subvolume SUBVOL4
on the primary system are replicated to SUBVOL3 on the backup system.
• The destination subvolume set must not have the same name as a different source subvolume
set. If they do, the updater process will fail at run-time. Consider the following example:
MAP NAMES TEST1.* TO TEST2.*
MAP NAMES TEST2.* TO TEST3.*
In this example, TEST2.* is used for both a source subvolume and a destination subvolume.
An updater logs errors whenever it detects invalid mapping string content or format. For
information about mapfile-related RDF events and RDFCOM error messages, see
“RDF Messages”
(page 365) and “RDFCOM Messages” (page 413) .
Examples of valid mapping strings include:
MAP NAMES HISSTUFF.* TO TEST10.*
MAP NAMES HERSTUFF.* TO TEST11.*
MAP NAMES THEIR*.* TO TEST12.*
Examples of invalid mapping strings, including disallowed reserved words, are:
MAP NAMES TEST*.* TO TEST*.*
MAP NAMES TEST1.* TO TEST*.*
MAP NAMES TEST1 TO TEST2
MAP NAMES $DATA01.TEST.* TO $DATA02.TEST1.*
MAP NAMES TEST1.* TO TEST2
MAP NAMES TEST1 TO TEST2.*
MAP NAMES TEST1.FILE1 TO TEST2.FILE1
MAP NAMES ZTMFAT.* TO TEST.*
MAP NAMES TEST.* TO ZTMFAT.*
MAP NAMES ZYS01.* TO TEST.*
MAP NAMES TEST.* TO ZYS01.*
MAP NAMES X01.* TO TEST.*
MAP NAMES Y01.* TO TEST.*
MAP NAMES Z01.* TO TEST.*
Once a mapfile has been created, these rules govern its use:
• You cannot modify the mapfile's path while RDF is running.
• Changes made to an existing mapfile do not take effect until the updater is stopped and
restarted.
• You cannot alter the mapfile path from the backup system through RDFCOM when the
primary system is accessible.
How an Updater Manages Filename Collisions
If you inadvertently map two subvolumes on the primary system to the same subvolume on the
backup system for an updater, the updater detects the filename collision, logs EMS event 927,
and abends. This approach prevents possible data corruption or disk failure.
To illustrate how a filename collision might occur, assume that the mapping string for the updater
that replicates from $DATA01 on the primary system to $DATA01 on the backup system is:
286 Subvolume Name Mapping