Oracle Database 11 g - Online Public Access Catalog

290 CHAPTER 6 ■ BACKUP AND RECOVERY• You must provide a network service name when connecting to the auxiliary instance,even if you’re performing the duplication on the same server, since you’re performing anetwork-based database duplication.• By default, RMAN will not copy the password file from the target to the duplicate destination.You must specify the password file clause inside the duplicate database command tocopy the password file.• In a Data Guard environment, the contents of the password file must be the same.■Note With the ever-increasing security concerns, most companies are adopting secure shell (SSH) as thecorporate standard for Unix shell access. Using SSH, you can remotely synchronize the password file (andeven automate this process using cron). The following tar command piped to SSH can be used to performsuch synchronization:cd $ORACLE_HOME/dbs; tar cvf – orapw$ORACLE_SID|ssh $REMOTE_HOST "cd $ORACLE_HOME/dbs; tar xvf –"The source database remains fully accessible to users while you’re performing the databaseduplication, which is yet another great feature of the active database duplication technique. Ofcourse, be prepared to take a slight hit on CPU usage and network bandwidth consumptionduring the datafile duplication.■Note In previous releases, RMAN couldn’t duplicate a tablespace that wasn’t made read/write after transportingthe tablespace. If you set the database compatibility to 11.0.0 or greater, RMAN will automaticallyduplicate a transportable tablespace whose status you didn’t change to read/write after the tablespace transport.Necessary Spfile ModificationsIn Oracle Database 10g, you didn’t copy the spfile as part of a database duplication process.You had to first copy the spfile to the destination server and modify it to suit the duplicate database’srequirements. In Oracle Database 11g, you can specify the spfile clause in the databaseduplication command for both the new active database duplication (network-enabled duplication)as well as traditional backup-based database duplication. By specifying the new spfileclause, you direct RMAN to copy the source database’s spfile to the destination server. For thisto happen, you must have started the source database with a server parameter file. BeforeRMAN processes the duplicate database command, it first copies over this spfile, modifies itbased on the settings in the spfile clause, and starts up the auxiliary instance with this modifiedserver parameter file. If you use the spfile command in your duplicate database command,you must start the auxiliary instance with a traditional text-based (init.ora) initializationparameter file (init.ora).When you duplicate a database, RMAN has to generate names for the duplicate database’sdatafiles, controlfiles, online redo log files, and tempfiles. If you’re using the same directory