oracle rconfig convert single instance to rac database

      rconfig 命令轉換單例項到rac 的文件介紹說明

Applies to:

Oracle Application Object Library - Version: 11.5.10 to 11.5.10
Information in this document applies to any platform.

Purpose

This FAQ explains the "rconfig" tool introduced in Oracle Database Version 10.2. This is also used extensively when Oracle E-Business Suite 11i Customers convert their Single Instance Database to RAC.

Questions and Answers

What is rconfig ?

rconfig is a command line tool introduced in Oracle Database 10g R2 to convert Single-Instance 10g R2 Database to RAC(Real Application Cluster). The other option is to use Convert to RAC option on the single-instance database target of Oracle Enterprise Manager Grid Control.

How does rconfig works ?

rconfig is located at $ORACLE_HOME/bin/. rconfig takes in a xml input file and convert the Single Instance database whose information is provided in the xml.This tool is documented in the and a sample xml can be found $ORACLE_HOME/assistants/rconfig/sampleXMLs/ConvertToRAC.xml.

rconfig performs following steps :

• Migrate the database to ASM storage (Only if ASM is specified as storage option in the configuration xml file above) 
• Create Database Instances on all nodes in the cluster 
• Configure Listener and NetService entries
• Configure and register CRS resources 
• Start the instances on all nodes in the cluster.

What are the prerequisites before we use rconfig ?

Before you convert a single-instance database to a RAC database using rconfig, ensure that the following conditions are met for each cluster node that you intend to make a RAC database node:

• Oracle Clusterware 10g Release 2 (10.2) is installed, configured, and running.
• Oracle Real Application Clusters 10g Release 2 (10.2) software is installed.
• The Oracle binary is enabled for RAC.
• Shared storage, either Oracle Cluster File System or ASM, is available and accessible from all nodes.
• User equivalence exists for the oracle user.

How to test rconfig before converting to RAC ?

Oracle 10g R2 Install has provided a sample rconfig input XML file called ConvertToRAC.xml at directory $ORACLE_HOME/assistants/rconfig/sampleXMLs. Make a copy of the sample XML file & make your own customised copy of input giving your Instance specific details. The Sample XML file includes comments to make understand how to edit each variable.

For testing purpose you need to modify the "Convert verify = "ONLY" option in the xml file.Then run the tool :

$ ./rconfig convert.xml

The Convert verify option in the ConvertToRAC.xml file has three options:

• Convert verify="YES": rconfig performs checks to ensure that the prerequisites for single-instance to RAC conversion have been met before it starts conversion
• Convert verify="NO": rconfig does not perform. prerequisite checks, and starts conversion
• Convert verify="ONLY" : rconfig only performs prerequisite checks; it does not start conversion after completing prerequisite checks
  

Where are the rconfig log files located ?

rconfig log files are located at  $ORACLE_HOME/cfgtoollogs/rconfig

Also one important thing to note is that rconfig re-writes the log file everytime you run the rconfig tool. So make sure have a copy in case you want to refer to the results of earlier run

 How to restart Rconfig ?

After running RCONFIG in Convert verify="YES" Mode, if you get any fatal error(e.g. Disk space not available, Some issue with 10g Parameters, Shared Storage Issues) which exits the rconfig tool & stops the conversion. You can restart the rconfig tool again by running the command " $ ./rconfig convert.xml ". This will perform. the clean-up operation on converted Instance or will delete the files created by earlier run. It again starts the process of conversion from start i.e. taking rman backup of Single Instance. After the conversion you can check the filesystem to verify if there is anything left from the previous failed run.