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

Operating and Monitoring RDF
Compaq NonStop™ RDF/IMP and IMPX System Management Manual—522204-001
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Changing Configuration Parameters
Changing Configuration Parameters
After RDF starts, you can change the following configuration parameters as the need
arises:
•
The priority at which each RDF process runs
•
The EMS log
•
The purger’s RETAINCOUNT
The RETAINCOUNT purger process configuration parameter specifies how many
image trail files must be retained on disk for each image trail.
The process priority and EMS log (collector) are the only configuration parameters that
can be altered while RDF is running. To change any other configuration parameters
(including RETAINCOUNT), you must first stop RDF as directed under Restarting RDF
in section 5.
To change parameter values, you access RDFCOM and use the ALTER command.
ALTER is a restricted command; it can be issued only by members of the super-user
group.
Process Priority
All configured RDF processes should run at a priority greater than that of any
application process. Furthermore, the RDF processes should run at priorities relative to
one another as follows:
•
On the primary system, the monitor and extractor processes can run at the same
priority but it is recommended that you set the extractor’s priority slightly lower than
that of the monitor.
•
On the backup system, the receiver process should run at a higher priority than any
updater process.
The STATUS RDF display shows the priority at which each RDF process is running.
Suppose this display indicates that the monitor currently runs at a priority of 165. To
change its priority to 170, use the ALTER command as follows:
]ALTER MONITOR PRIORITY 170
EMS Logs (Collectors)
In an RDF configuration, two EMS logs (collectors) exist: one at the primary system
and the other at the backup system. The log on the primary system is used by the
monitor, RDFCOM, and extractor processes. The log on the backup system is used by
the receiver and updater processes. Both logs have the same name.
To redirect messages from the current EMS log to the log named NEWLOG (on the
control subvolume CHICAGO), enter:
]ALTER RDF LOGFILE $SYSTEM.CHICAGO.NEWLOG