HP NonStop RDF, Руководство по управлению

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LOGFILE
ems-collector-name
specifies a device (EMS collector) that is to receive messages from RDF. The specified device
must exist on both the primary and backup systems. The default is $0.
The device on the primary system receives log messages from the extractor and monitor
processes plus RDFCOM messages that are logged in message 835 and messages from
RDFNET, if configured.
The device on the backup system receives log messages from the receiver, purger, and all
updater processes (plus RDFCOM messages that are logged in message 835).
UPDATERDELAY
delay
specifies how many seconds (from 1 to 10) the updater processes should delay upon reaching
the logical EOF in the image trail before attempting a new read. The default is 10 seconds.
The default updater delay is the recommended value for virtually all users of RDF. Lowering
it could adversely affect other updaters’ performance.
You can alter the UPDATERDELAY value while updaters are running by using the ALTER
RDF UPDATERDELAY command.
UPDATERTXTIME
tx-time
specifies the maximum transaction duration (in seconds, from 10 to 300) for all updater
processes. The default is 60 seconds.
RDF updaters operate in transaction mode. Updater transactions are essentially long-running
transactions that pin audit trail files on the backup system and can affect the duration of
backout operations if an updater transaction aborts for any reason.
The default value is recommended for RDF environments with heavy updater activity
(aggregate updater throughput greater than 300 kb/second). Raising the
tx-time
in such
environments could adversely affect TMF performance on the backup system.
In RDF environments with low to moderate updater activity and where no other transaction
activity is occurring on the backup system, you could raise the
tx-time
without affecting
TMF performance on the backup system.
UPDATERRTDWARNING
rtd-time
specifies the RTD warning threshold (in seconds, 0 or greater) for all configured updaters.
The default is 60 seconds.
This threshold is used by the STATUS RTDWARNING command to determine which
updaters, if any, are to be included in its display. Besides the monitor process (and perhaps
the extractor), the display includes only those updaters, if any, whose RTD exceeds the
configured updater RTD warning threshold.
UPDATEROPEN
access-mode
specifies the access mode (PROTECTED, PROTECTED OPEN, or SHARED) that updaters
use when opening database files. The default is PROTECTED.
PROTECTED access is strongly recommended at all times, except when you specifically want
to take online dumps or do reloads of the backup database with the updaters running. Before
you start an online dump or a reload operation, you should alter the UPDATEROPEN mode
from PROTECTED to SHARED. After the dump or reload has finished, you should change
the UPDATEROPEN mode back to SHARED. See the discussion in Chapter 3 for the issues
involved, including the meaning of PROTECTED OPEN.
To change the configured updater
access-mode
:
1. Issue a STOP UPDATE command.
2. Issue an ALTER RDF UPDATEROPEN command specifying the desired access mode.
3. Issue a START UPDATE command.
RDFCOM Commands 229