RDF System Management Manual

Preparing the RDF Environment
HP NonStop RDF System Management Manual—524388-003
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Configuring an SMF Environment on the Backup
RDF System
•
Place the SMF catalog in the default SMF catalog subvolume on a volume that is
protected by RDF.
The extractor automatically filters out changes to the SMF catalog if the catalog is
in the default SMF catalog subvolume. If you store the catalog in your own
subvolume, the extractor will try to replicate changes to the catalog, which could
have an adverse affect on RDF and any SMF catalogs with the same subvolume
name on the backup system.
•
Place the SMF catalog in a subvolume that is explicitly excluded from RDF
protection (the INCLUDE and EXCLUDE clauses are described in Section 11,
Subvolume- and File-Level Replication).
Configuring an SMF Environment on the Backup RDF System
RDF supports the replication to SMF logical volumes on the backup system, with the
following restrictions:
1. When replicating to an SMF logical volume, the logical volume must belong to an
SMF pool that contains 15 or fewer physical volumes, hence each updater can
apply audit to up to 15 physical disks.
2. The RDF/IMP product limits the total number of physical or virtual UPDATE
volumes to 255. RDF/IMPX and ZLT have no such limitation, other than the limit of
255 updaters and each updater only being able to work on a maximum of 15
physical volumes.
3. Image trail volumes cannot reside on SMF logical volumes.
There are no restrictions on the placement of SMF catalog files on the backup system.
If the backup system could ever become a primary (such as after an RDF takeover, for
example, or as the result of a planned switchover), then the restrictions described in
the preceding topic for primary systems also apply.
RDF replicates Enscribe file creations when audited Enscribe files are created on RDF
protected volumes. When the UPDATEVOLUME is a virtual disk, the updater process
tells SMF to create the file and register it in the SMF catalog. When the
UPDATEVOLUME is a virtual disk comprised of multiple physical disks, SMF decides
which physical disk will store the file. You have no control over where a new Enscribe
file is created. Refer to the HP NonStop Storage Management Foundation (SMF)
Management Manual for further information about the factors SMF uses to decide on
the file placement.
Note. A single updater process only works on 500 files at any time. If you have a virtual disk
that has many physical disks in its pool, and if the number of files that need to be updated by
the updater assigned to that virtual disk exceeds 500, the updater will close some files in order
to work on files it does not already have open. If this updater must regularly work on more than
500 files, the performance of the updater is impacted. For optimal updater performance,
ensure that no single updater must work on more than 500 files on a regular basis. This
condition might mean that you have to reduce the number of physical disks in a pool.